Windows Disk Management & Troubleshooting Quick Reference

Created: 2026-08-12 Version: 1.0 Audience: IT Administrators, SRE Engineers, Windows System Administrators

Table of Contents

1. Disk Identification & Information
2. Partitioning
3. Filesystems
4. Storage Spaces
5. SMART & Health Monitoring
6. Disk Performance
7. Troubleshooting & Recovery
8. SSD-Specific
9. BitLocker
10. Best Practices

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1. Disk Identification & Information

Disk Management GUI

Open via diskmgmt.msc or Win+X > Disk Management. Provides a visual layout of all disks, partitions, volumes, and their statuses (Healthy, Failed, Online, Offline).

diskpart

REM List all disks
diskpart
DISKPART> list disk

REM Select a disk and show details
DISKPART> select disk 0
DISKPART> detail disk

REM List all volumes
DISKPART> list volume

REM List partitions on selected disk
DISKPART> select disk 0
DISKPART> list partition

PowerShell Cmdlets

# All physical disks (model, media type, health, size)
Get-PhysicalDisk | Format-Table DeviceId, FriendlyName, MediaType, Size, HealthStatus

# Logical disks (partitions, style, operational status)
Get-Disk | Format-Table Number, FriendlyName, PartitionStyle, OperationalStatus, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}

# All partitions
Get-Partition | Format-Table DiskNumber, PartitionNumber, DriveLetter, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}, Type

# All volumes (drive letter, filesystem, size, free space)
Get-Volume | Format-Table DriveLetter, FileSystemLabel, FileSystem, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}, @{N='FreeGB';E={[math]::Round($_.SizeRemaining/1GB,2)}}, HealthStatus

# Disk to partition to volume mapping
Get-Disk | ForEach-Object {
    $disk = $_
    Get-Partition -DiskNumber $disk.Number | ForEach-Object {
        [PSCustomObject]@{
            Disk       = $disk.Number
            Model      = $disk.FriendlyName
            Partition  = $_.PartitionNumber
            Letter     = $_.DriveLetter
            SizeGB     = [math]::Round($_.Size/1GB,2)
            Type       = $_.Type
        }
    }
} | Format-Table -AutoSize

WMI / CIM Queries

# Disk drives (model, serial, interface, firmware)
Get-CimInstance Win32_DiskDrive | Select-Object DeviceID, Model, SerialNumber, InterfaceType, FirmwareRevision, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}

# Logical disks (classic)
Get-CimInstance Win32_LogicalDisk | Select-Object DeviceID, VolumeName, FileSystem, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}, @{N='FreeGB';E={[math]::Round($_.FreeSpace/1GB,2)}}

# Disk partitions
Get-CimInstance Win32_DiskPartition | Select-Object Name, Type, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}

REM CMD equivalent (legacy)
wmic diskdrive get model,serialNumber,interfaceType,size,status
wmic logicaldisk get caption,description,filesystem,size,freespace

Device Manager

Open devmgmt.msc and expand Disk drives to see physical disk hardware, driver info, and hardware IDs. Right-click a disk > Properties > Details > Hardware Ids to identify the exact model and firmware revision. The Events tab shows recent disk-related events.

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2. Partitioning

MBR vs GPT

Feature	MBR	GPT
Max disk size	2 TB	18 EB (exabytes)
Max primary partitions	4 (or 3 + extended)	128
Boot mode	BIOS/Legacy	UEFI
Partition table backup	None	Secondary GPT header at end of disk
Data integrity	None	CRC32 checksums
OS support	All Windows	Windows 7+ (data), Windows 8+ (boot)

UEFI Boot Requirement

Windows can only boot from a GPT disk in UEFI mode. For BIOS/Legacy mode, the boot disk must be MBR. Data disks can use GPT regardless of boot mode.

diskpart: Partition Operations

REM === Create a primary partition ===
diskpart
DISKPART> select disk 1
DISKPART> create partition primary size=51200
DISKPART> format fs=ntfs label="Data" quick
DISKPART> assign letter=D

REM === Extend a partition (unallocated space must be adjacent and to the right) ===
DISKPART> select volume D
DISKPART> extend size=10240

REM === Shrink a partition ===
DISKPART> select volume C
DISKPART> shrink desired=20480 minimum=10240

REM Query how much can be shrunk
DISKPART> shrink querymax

REM === Delete a partition ===
DISKPART> select disk 1
DISKPART> select partition 2
DISKPART> delete partition

REM Force-delete a protected partition (OEM, recovery)
DISKPART> delete partition override

REM === Initialize a new disk ===
DISKPART> select disk 2
DISKPART> clean
DISKPART> convert gpt
DISKPART> create partition primary
DISKPART> format fs=ntfs label="NewDisk" quick
DISKPART> assign letter=E

PowerShell: Partition Operations

# Initialize a new raw disk as GPT
Initialize-Disk -Number 2 -PartitionStyle GPT

# Create a new partition using all available space
New-Partition -DiskNumber 2 -UseMaximumSize -AssignDriveLetter

# Create a partition with a specific size and drive letter
New-Partition -DiskNumber 2 -Size 50GB -DriveLetter E

# Format the new partition
Format-Volume -DriveLetter E -FileSystem NTFS -NewFileSystemLabel "Data" -Confirm:$false

# Resize (extend) a partition
Resize-Partition -DriveLetter D -Size (Get-PartitionSupportedSize -DriveLetter D).SizeMax

# Resize (shrink) a partition — set target size, not shrink amount
$current = Get-Partition -DriveLetter C
Resize-Partition -DriveLetter C -Size ($current.Size - 20GB)

# Remove a partition
Remove-Partition -DiskNumber 1 -PartitionNumber 3 -Confirm:$false

# One-liner: initialize, partition, and format a new disk
Initialize-Disk 2 -PartitionStyle GPT -PassThru |
    New-Partition -UseMaximumSize -AssignDriveLetter |
    Format-Volume -FileSystem NTFS -NewFileSystemLabel "Backup"

Special Partitions

Partition	Purpose	Typical Size	Notes
EFI System Partition (ESP)	UEFI boot loader files	100-500 MB	FAT32, mounted at \EFI
Microsoft Reserved (MSR)	GPT management area	16-128 MB	No filesystem, invisible in Disk Management
Recovery Partition	Windows RE (WinRE)	500-1000 MB	NTFS, hidden, no drive letter
OEM Partition	Manufacturer recovery tools	Varies	Vendor-specific, can be deleted with override

# View all partitions including hidden ones
Get-Partition -DiskNumber 0 | Select-Object PartitionNumber, GptType, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}, Type, IsHidden

# Common GPT type GUIDs
# EFI System:  {c12a7328-f81f-11d2-ba4b-00a0c93ec93b}
# MSR:         {e3c9e316-0b5c-4db8-817d-f92df00215ae}
# Basic Data:  {ebd0a0a2-b9e5-4433-87c0-68b6b72699c7}
# Recovery:    {de94bba4-06d1-4d40-a16a-bfd50179d6ac}

Converting MBR to GPT

REM In-place conversion for Windows 10 1703+ (non-destructive for boot disks)
REM Run from Windows PE or Recovery Environment
mbr2gpt /validate /disk:0
mbr2gpt /convert /disk:0

REM Allow conversion while OS is running (risky, use /allowFullOS)
mbr2gpt /convert /disk:0 /allowFullOS

Before MBR to GPT Conversion

1. Back up all data on the disk.
2. Ensure firmware supports UEFI boot.
3. Change BIOS settings from Legacy to UEFI after conversion.
4. mbr2gpt only works on boot disks with at most 3 primary partitions.
5. For data-only disks, use diskpart clean + convert gpt (destroys data) or third-party tools for non-destructive conversion.

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3. Filesystems

Filesystem Comparison

Feature	NTFS	ReFS	exFAT	FAT32
Max volume size	256 TB (practical)	35 PB	128 PB	2 TB
Max file size	256 TB	35 PB	128 PB	4 GB
Journaling	Yes	Yes (integrity streams)	No	No
Permissions (ACL)	Yes	Yes	No	No
Compression	Yes	No	No	No
Encryption (EFS)	Yes	No	No	No
Deduplication	Yes (Server)	Yes (Server)	No	No
BitLocker	Yes	No	Yes (Win 10+)	Yes
Cross-platform	Linux (rw), macOS (ro)	Windows only	Universal	Universal
Best for	OS drives, general use	Storage Spaces, backups	USB drives, SD cards	Legacy devices

Format Commands

REM CMD: format a volume
format D: /FS:NTFS /Q /V:DataDrive
format E: /FS:exFAT /Q /V:USBDrive
format F: /FS:FAT32 /Q /V:Legacy

# PowerShell: format a volume
Format-Volume -DriveLetter D -FileSystem NTFS -NewFileSystemLabel "DataDrive" -Confirm:$false
Format-Volume -DriveLetter E -FileSystem exFAT -NewFileSystemLabel "USBDrive" -Confirm:$false

# Format with specific allocation unit size (cluster size)
Format-Volume -DriveLetter D -FileSystem NTFS -AllocationUnitSize 65536 -NewFileSystemLabel "LargeFiles"

Drive Letters and Mount Points

# Assign a drive letter
Set-Partition -DiskNumber 1 -PartitionNumber 2 -NewDriveLetter G

# Remove a drive letter (make the volume accessible only via mount point)
Remove-PartitionAccessPath -DiskNumber 1 -PartitionNumber 2 -AccessPath "G:\"

# Mount a volume to a folder (NTFS mount point)
Add-PartitionAccessPath -DiskNumber 1 -PartitionNumber 2 -AccessPath "C:\Mounts\DataDrive"

# List all mount points
Get-Volume | Where-Object { $_.DriveLetter -eq $null } | ForEach-Object {
    $vol = $_
    Get-Partition | Where-Object { $_.AccessPaths -match $vol.UniqueId } |
        Select-Object DiskNumber, PartitionNumber, AccessPaths
}

REM diskpart: change drive letter
diskpart
DISKPART> select volume 3
DISKPART> assign letter=G

REM diskpart: remove drive letter
DISKPART> select volume 3
DISKPART> remove letter=G

REM mountvol: create a mount point
mountvol C:\Mounts\DataDrive \\?\Volume{GUID}\

REM mountvol: list volume GUIDs
mountvol

Drive Letter Persistence

Drive letter assignments are stored in the registry at HKLM\SYSTEM\MountedDevices. If a drive letter is not sticking after reboot, check that no other device is claiming the same letter and that the MountedDevices entries are correct.

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4. Storage Spaces

Overview

Storage Spaces pools multiple physical disks into a single logical storage pool. Virtual disks (storage spaces) are created from the pool with configurable resiliency.

Layout	Min Disks	Fault Tolerance	Space Efficiency	Best For
Simple	1	None	100%	Temporary data, performance
Two-way Mirror	2	1 disk failure	50%	OS volumes, critical data
Three-way Mirror	5	2 disk failures	33%	High availability
Parity	3	1 disk failure	67% (3 disks)	Archive, sequential workloads
Dual Parity	7	2 disk failures	71%+ (7 disks)	Large archive pools

Creating Storage Spaces via PowerShell

# Step 1: Identify available physical disks (must show CanPool = True)
Get-PhysicalDisk -CanPool $true | Format-Table DeviceId, FriendlyName, MediaType, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}

# Step 2: Create a storage pool
$disks = Get-PhysicalDisk -CanPool $true
New-StoragePool -FriendlyName "DataPool" -StorageSubSystemFriendlyName "Windows Storage*" -PhysicalDisks $disks

# Step 3: Create a virtual disk (two-way mirror, thin provisioning)
New-VirtualDisk -StoragePoolFriendlyName "DataPool" -FriendlyName "MirrorDisk" -ResiliencySettingName Mirror -UseMaximumSize

# With specific size and provisioning type
New-VirtualDisk -StoragePoolFriendlyName "DataPool" -FriendlyName "MirrorDisk" `
    -ResiliencySettingName Mirror `
    -Size 500GB `
    -ProvisioningType Thin `
    -NumberOfColumns 2

# Step 4: Initialize, partition, and format
Get-VirtualDisk -FriendlyName "MirrorDisk" | Get-Disk | Initialize-Disk -PartitionStyle GPT -PassThru |
    New-Partition -UseMaximumSize -AssignDriveLetter |
    Format-Volume -FileSystem ReFS -NewFileSystemLabel "MirrorData"

Managing Storage Spaces

# List all storage pools
Get-StoragePool | Where-Object IsPrimordial -eq $false | Format-Table FriendlyName, HealthStatus, OperationalStatus, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}

# List virtual disks in a pool
Get-VirtualDisk | Format-Table FriendlyName, ResiliencySettingName, OperationalStatus, HealthStatus, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}

# Check physical disk assignment in a pool
Get-StoragePool -FriendlyName "DataPool" | Get-PhysicalDisk | Format-Table DeviceId, FriendlyName, MediaType, HealthStatus, Usage

# Add a new physical disk to an existing pool
$newDisk = Get-PhysicalDisk -CanPool $true | Where-Object DeviceId -eq 3
Add-PhysicalDisk -StoragePoolFriendlyName "DataPool" -PhysicalDisks $newDisk

# Remove a virtual disk
Remove-VirtualDisk -FriendlyName "MirrorDisk" -Confirm:$false

# Remove a storage pool (remove all virtual disks first)
Remove-StoragePool -FriendlyName "DataPool" -Confirm:$false

# Repair a degraded virtual disk (after replacing a failed disk)
Repair-VirtualDisk -FriendlyName "MirrorDisk"

Storage Tiers (SSD + HDD)

# Create storage tiers in a pool (Server OS or Windows 10/11 with Storage Spaces)
$pool = Get-StoragePool -FriendlyName "DataPool"

# Define SSD tier
New-StorageTier -StoragePoolFriendlyName "DataPool" -FriendlyName "SSD_Tier" -MediaType SSD -ResiliencySettingName Mirror

# Define HDD tier
New-StorageTier -StoragePoolFriendlyName "DataPool" -FriendlyName "HDD_Tier" -MediaType HDD -ResiliencySettingName Parity

# Create a tiered virtual disk
$ssdTier = Get-StorageTier -FriendlyName "SSD_Tier"
$hddTier = Get-StorageTier -FriendlyName "HDD_Tier"

New-VirtualDisk -StoragePoolFriendlyName "DataPool" -FriendlyName "TieredDisk" `
    -StorageTiers $ssdTier, $hddTier `
    -StorageTierSizes 50GB, 200GB `
    -WriteCacheSize 5GB

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5. SMART & Health Monitoring

PowerShell Health Checks

# Physical disk health overview
Get-PhysicalDisk | Select-Object DeviceId, FriendlyName, MediaType, BusType, HealthStatus, OperationalStatus, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}

# Detailed SMART-like reliability counters
Get-PhysicalDisk | Get-StorageReliabilityCounter | Format-List *

# Key counters to watch
Get-PhysicalDisk | ForEach-Object {
    $disk = $_
    $counter = $_ | Get-StorageReliabilityCounter
    [PSCustomObject]@{
        Disk              = $disk.FriendlyName
        Temperature       = $counter.Temperature
        Wear              = $counter.Wear
        ReadErrors        = $counter.ReadErrorsTotal
        WriteErrors       = $counter.WriteErrorsTotal
        PowerOnHours      = $counter.PowerOnHours
        StartStopCycles   = $counter.StartStopCycleCount
        ReadLatencyMax    = $counter.ReadLatencyMax
        WriteLatencyMax   = $counter.WriteLatencyMax
    }
}

# Check NVMe-specific health (Windows 10 1903+)
Get-PhysicalDisk | Where-Object BusType -eq NVMe | Get-StorageReliabilityCounter |
    Select-Object DeviceId, Temperature, Wear, ReadErrorsTotal, WriteErrorsTotal

WMI Disk Status

REM Quick SMART status check (returns "OK" or "Pred Fail")
wmic diskdrive get model,status,serialNumber

# CIM equivalent
Get-CimInstance Win32_DiskDrive | Select-Object Model, SerialNumber, Status

CrystalDiskInfo

CrystalDiskInfo is a free tool that reads raw SMART attributes.

• Download: https://crystalmark.info/en/software/crystaldiskinfo/
• Portable version available (no install needed)
• Monitors: Reallocated Sectors, Pending Sectors, Temperature, Power-On Hours, Wear Leveling Count
• Can run as a service for alerting (System > Resident / Startup)

SMART Limitations

SMART status "OK" does not guarantee the disk is healthy. A disk can fail without SMART warning. Use SMART as one signal among many (performance metrics, error logs, age). SMART is particularly unreliable for predicting sudden failures.

Event Viewer: Disk-Related Events

Open eventvwr.msc and check Windows Logs > System and Applications and Services Logs > Microsoft > Windows > StorDiag.

Event ID	Source	Severity	Meaning
7	Disk	Error	Bad block detected on disk
9	Disk	Error	Controller not responding; device timeout
11	Disk	Error	Controller error (I/O failed)
15	Disk	Error	Disk not ready for access
51	Disk	Warning	Paging error during I/O operation
52	Disk	Warning	Disk driver detected a firmware bug
129	storahci	Warning	Reset to device (NVMe/AHCI timeout)
153	Disk	Warning	Disk retry on I/O operation
154	Disk	Warning	Disk surprise removal
157	Disk	Error	Disk has been surprise removed

# Query disk error events from the last 7 days
Get-WinEvent -FilterHashtable @{
    LogName   = 'System'
    ProviderName = 'disk','storahci','stornvme','partmgr','ntfs'
    Level     = 1,2,3   # Critical, Error, Warning
    StartTime = (Get-Date).AddDays(-7)
} | Format-Table TimeCreated, Id, LevelDisplayName, Message -Wrap

# Count disk errors per Event ID
Get-WinEvent -FilterHashtable @{LogName='System'; ProviderName='disk'; Level=1,2,3; StartTime=(Get-Date).AddDays(-30)} |
    Group-Object Id | Select-Object Count, Name | Sort-Object Count -Descending

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6. Disk Performance

Performance Monitor (perfmon)

Key disk counters to monitor in perfmon.msc:

Counter	Object	Warning Threshold	Description
% Disk Time	PhysicalDisk	>80% sustained	Time disk is busy
Avg. Disk Queue Length	PhysicalDisk	>2 per spindle	Pending I/O requests
Avg. Disk sec/Read	PhysicalDisk	>20ms (HDD), >10ms (SSD)	Read latency
Avg. Disk sec/Write	PhysicalDisk	>20ms (HDD), >10ms (SSD)	Write latency
Disk Reads/sec	PhysicalDisk	Baseline-dependent	IOPS (read)
Disk Writes/sec	PhysicalDisk	Baseline-dependent	IOPS (write)
Disk Bytes/sec	PhysicalDisk	Baseline-dependent	Throughput
Current Disk Queue Length	PhysicalDisk	>2	Instantaneous queue depth

REM Collect disk performance data for 60 seconds (1-second interval)
typeperf "\PhysicalDisk(*)\Avg. Disk sec/Read" "\PhysicalDisk(*)\Avg. Disk sec/Write" "\PhysicalDisk(*)\Disk Reads/sec" "\PhysicalDisk(*)\Disk Writes/sec" -si 1 -sc 60 -o disk_perf.csv

PowerShell Performance Queries

# Real-time disk I/O per process (top 10)
Get-Process | Sort-Object -Property @{E={$_.IO_DATA_BYTES_PER_SEC}} -Descending |
    Select-Object -First 10 Name, Id,
        @{N='ReadMB';E={[math]::Round(($_.ReadTransferCount)/1MB,2)}},
        @{N='WriteMB';E={[math]::Round(($_.WriteTransferCount)/1MB,2)}}

# Performance counter snapshot
Get-Counter '\PhysicalDisk(*)\Avg. Disk sec/Read','\PhysicalDisk(*)\Avg. Disk sec/Write','\PhysicalDisk(*)\Current Disk Queue Length' |
    ForEach-Object { $_.CounterSamples } | Format-Table Path, CookedValue

# Continuous monitoring (5-second intervals, 12 samples)
Get-Counter '\PhysicalDisk(_Total)\% Disk Time','\PhysicalDisk(_Total)\Avg. Disk Queue Length' -SampleInterval 5 -MaxSamples 12

Resource Monitor

Open resmon.exe and go to the Disk tab for real-time per-process I/O activity with read/write speeds and response times.

Windows System Assessment Tool (winsat)

REM Run disk assessment
winsat disk -drive C

REM Sequential read/write test
winsat disk -seq -read -drive C
winsat disk -seq -write -drive C

REM Random read/write test
winsat disk -ran -read -drive C
winsat disk -ran -write -drive C

DiskSpd Benchmarking

DiskSpd is Microsoft's recommended storage benchmarking tool (successor to SQLIO).

Download: https://github.com/microsoft/diskspd

REM Sequential read test: 8 threads, 64KB blocks, 30 seconds, 10GB file
diskspd -b64K -d30 -o8 -t8 -h -r -w0 -L -Z1M -c10G C:\diskspd_test.dat

REM Random 4K read/write mix (70/30): simulates OLTP workload
diskspd -b4K -d60 -o32 -t4 -r -w30 -L -Z1M -c2G C:\diskspd_test.dat

REM Sequential write test
diskspd -b64K -d30 -o8 -t8 -h -r -w100 -L -Z1M -c10G C:\diskspd_test.dat

DiskSpd Key Parameters:

Parameter	Meaning
-b<size>	Block size (4K, 64K, 1M)
-d<seconds>	Test duration
-o<count>	Outstanding I/O per thread (queue depth)
-t<count>	Threads per target file
-r	Random I/O (omit for sequential)
-w<percent>	Write percentage (0 = all reads, 100 = all writes)
-L	Capture latency statistics
-h	Disable OS caching (hardware caching only)
-Z<size>	Entropy seed size for write buffer
-c<size>	Create file of specified size

DiskSpd Best Practices

Always use -h to bypass the OS cache for realistic results. Run tests multiple times and average the results. Use -Z1M or larger to avoid compression effects on SSDs with hardware compression. Delete the test file after benchmarking.

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7. Troubleshooting & Recovery

chkdsk (Check Disk)

REM Check for errors (read-only, no fix)
chkdsk D:

REM Fix filesystem errors
chkdsk D: /f

REM Fix errors + scan for bad sectors and recover readable data
chkdsk D: /r

REM Force dismount before checking (use on locked volumes)
chkdsk D: /x

REM Re-evaluate bad clusters (NTFS only, implies /r)
chkdsk D: /b

REM Scan online (NTFS, Windows 8+, minimal downtime)
chkdsk D: /scan

REM Schedule chkdsk on boot for system volume
chkdsk C: /f
REM (Responds "yes" when prompted to schedule on next restart)

# PowerShell equivalent
Repair-Volume -DriveLetter D -Scan                 # Read-only scan
Repair-Volume -DriveLetter D -OfflineScanAndFix     # Offline fix
Repair-Volume -DriveLetter D -SpotFix               # Online spot fix (Server 2012+/Win 8+)

chkdsk /r Runtime

chkdsk /r can take hours on large volumes because it scans every sector. For SSDs, bad sector recovery is less relevant; use /f or /scan instead. Never run /r on an SSD unless you suspect controller-level issues.

SFC and DISM

REM System File Checker - scan and repair protected system files
sfc /scannow

REM If SFC fails, repair the Windows image first with DISM
DISM /Online /Cleanup-Image /CheckHealth
DISM /Online /Cleanup-Image /ScanHealth
DISM /Online /Cleanup-Image /RestoreHealth

REM Then re-run SFC
sfc /scannow

REM DISM with a known-good source (mounted ISO or WIM)
DISM /Online /Cleanup-Image /RestoreHealth /Source:D:\sources\install.wim

Common Disk Error States

Disk State	Cause	Resolution
Offline	Disk policy, name collision, or disk error	Right-click > Online in Disk Management, or Set-Disk -Number X -IsOffline $false
Missing	Disk was removed or failed	Check physical connection; rescan: Update-StorageProviderCache
Foreign	Disk was moved from another system (dynamic disks)	Right-click > Import Foreign Disks in Disk Management
Not Initialized	New disk, no partition table	Initialize via Disk Management or Initialize-Disk -Number X -PartitionStyle GPT
Read Only	Disk policy or hardware write-protect	Set-Disk -Number X -IsReadOnly $false or check physical switch
No Media	Card reader with no card inserted	Normal; insert media

# Bring an offline disk online
Set-Disk -Number 2 -IsOffline $false

# Clear read-only flag
Set-Disk -Number 2 -IsReadOnly $false

# Set SAN policy to online all new disks (useful for VMs and SANs)
# Run in elevated PowerShell:
Set-StorageSetting -NewDiskPolicy OnlineAll

Disk Signature Collision

When two disks have the same MBR signature (common when cloning), one goes offline.

REM Fix via diskpart: assign a new signature
diskpart
DISKPART> select disk 1
DISKPART> uniqueid disk
DISKPART> uniqueid disk id=AABBCCDD

# View disk signatures
Get-Disk | Select-Object Number, FriendlyName, Signature, Guid, OperationalStatus

Handling Full Disk

# Find largest files on a volume
Get-ChildItem -Path C:\ -Recurse -File -ErrorAction SilentlyContinue |
    Sort-Object Length -Descending |
    Select-Object -First 20 @{N='SizeMB';E={[math]::Round($_.Length/1MB,2)}}, FullName

# Find largest folders (top-level)
Get-ChildItem -Path C:\ -Directory -ErrorAction SilentlyContinue | ForEach-Object {
    [PSCustomObject]@{
        Folder = $_.FullName
        SizeGB = [math]::Round((Get-ChildItem $_.FullName -Recurse -File -ErrorAction SilentlyContinue |
            Measure-Object Length -Sum).Sum / 1GB, 2)
    }
} | Sort-Object SizeGB -Descending | Select-Object -First 15

# Windows Disk Cleanup (interactive)
cleanmgr /d C:

# Disk Cleanup with all options pre-selected (sageset creates profile, sagerun executes it)
cleanmgr /sageset:1
cleanmgr /sagerun:1

# Clear Windows Update cache
Stop-Service wuauserv
Remove-Item -Path "C:\Windows\SoftwareDistribution\Download\*" -Recurse -Force
Start-Service wuauserv

# Clear temp files
Remove-Item -Path "$env:TEMP\*" -Recurse -Force -ErrorAction SilentlyContinue
Remove-Item -Path "C:\Windows\Temp\*" -Recurse -Force -ErrorAction SilentlyContinue

# DISM: clean up old component store versions
DISM /Online /Cleanup-Image /StartComponentCleanup /ResetBase

GUI Tools for disk space analysis:

• WinDirStat - classic treemap visualization (https://windirstat.net)
• TreeSize Free - fast, Explorer-integrated (https://www.jam-software.com/treesize_free)
• WizTree - fastest scanner (reads MFT directly) (https://wiztree.com)

Windows Recovery Environment (WinRE)

Access via Settings > System > Recovery > Advanced startup, or boot from installation media and choose Repair your computer.

Available tools in WinRE:

• Command Prompt - run chkdsk, sfc, diskpart, bcdedit, bootrec
• Startup Repair - automatic boot issue fix
• System Restore - revert to a restore point
• System Image Recovery - restore from a full backup image
• UEFI Firmware Settings - direct access to BIOS/UEFI

REM Common WinRE commands

REM Fix boot records
bootrec /fixmbr
bootrec /fixboot
bootrec /rebuildbcd

REM Repair EFI boot (when bootrec /fixboot fails with "access denied")
diskpart
DISKPART> select disk 0
DISKPART> list volume
REM Identify the EFI partition (FAT32, ~100MB)
DISKPART> select volume 2
DISKPART> assign letter=S
DISKPART> exit

cd /d S:\EFI\Microsoft\Boot
ren BCD BCD.bak
bcdboot C:\Windows /s S: /f UEFI

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8. SSD-Specific

TRIM

TRIM tells the SSD which blocks are no longer in use so the controller can manage wear leveling and garbage collection efficiently.

# Check if TRIM is enabled (RetrimEnabled should be True)
fsutil behavior query DisableDeleteNotify
# 0 = TRIM enabled, 1 = TRIM disabled

# Verify optimization settings
Get-Volume | Select-Object DriveLetter, FileSystem, @{N='MediaType';E={(Get-PhysicalDisk | Where-Object DeviceId -eq (Get-Partition -DriveLetter $_.DriveLetter -ErrorAction SilentlyContinue | Select-Object -ExpandProperty DiskNumber -ErrorAction SilentlyContinue)).MediaType}}

# Manually trigger TRIM/optimization
Optimize-Volume -DriveLetter C -ReTrim -Verbose

REM Optimize (TRIM for SSD, defrag for HDD)
defrag C: /O

REM Force retrim
defrag C: /L

REM Check optimization status
dfrgui

Do Not Defragment SSDs

Windows automatically runs TRIM on SSDs via the scheduled "Optimize Drives" task. Traditional defragmentation is unnecessary and harmful to SSDs. The defrag /O command is safe because it detects the media type and runs TRIM instead of defragmentation.

NVMe Management

# Identify NVMe drives
Get-PhysicalDisk | Where-Object BusType -eq NVMe |
    Select-Object DeviceId, FriendlyName, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}, HealthStatus, OperationalStatus

# NVMe-specific health data
Get-PhysicalDisk | Where-Object BusType -eq NVMe | Get-StorageReliabilityCounter |
    Select-Object DeviceId, Temperature, Wear, ReadErrorsTotal, WriteErrorsTotal, PowerOnHours

# NVMe namespace information (Windows 11 / Server 2022+)
Get-Disk | Where-Object BusType -eq NVMe | Select-Object Number, FriendlyName, FirmwareVersion, AdapterSerialNumber

REM List NVMe controllers (requires elevated CMD)
wmic path Win32_NVMeController get DeviceId,Name,DriverVersion

SSD Firmware Updates

1. Identify the SSD model: Get-PhysicalDisk | Select-Object FriendlyName, FirmwareVersion
2. Download the firmware update tool from the manufacturer's website
3. Common manufacturer tools:
4. Samsung: Samsung Magician
5. Crucial/Micron: Crucial Storage Executive
6. Western Digital / SanDisk: WD Dashboard
7. Intel: Intel Memory and Storage Tool (MAS CLI)
8. Kingston: Kingston SSD Manager
9. Seagate: SeaTools

Firmware Update Precautions

Always back up data before firmware updates. Some updates require a power cycle; never interrupt the update process. Use a UPS or ensure stable power. Some NVMe firmware updates require a bootable ISO.

Over-Provisioning

Over-provisioning reserves a portion of SSD capacity for the controller to use for wear leveling, garbage collection, and bad block replacement.

• Most consumer SSDs have 7-10% built-in over-provisioning
• Enterprise SSDs typically have 20-28%
• You can manually increase OP by leaving unpartitioned space at the end of the drive
• Some manufacturer tools (Samsung Magician, Crucial Storage Executive) offer a dedicated OP setting

# Check current partitioned vs total capacity
$disk = Get-Disk -Number 0
$partitioned = (Get-Partition -DiskNumber 0 | Measure-Object Size -Sum).Sum
$total = $disk.Size
$opPercent = [math]::Round((($total - $partitioned) / $total) * 100, 1)
Write-Host "Total: $([math]::Round($total/1GB,2)) GB, Partitioned: $([math]::Round($partitioned/1GB,2)) GB, Unallocated (OP): $opPercent%"

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9. BitLocker

Status and Information

# Check BitLocker status for all volumes
Get-BitLockerVolume | Format-Table MountPoint, VolumeStatus, EncryptionMethod, EncryptionPercentage, ProtectionStatus, LockStatus, KeyProtector

# Detailed status for a specific volume
Get-BitLockerVolume -MountPoint "C:" | Format-List *

REM manage-bde: check status
manage-bde -status
manage-bde -status C:

Enable BitLocker

# Enable BitLocker with TPM protector (typical for OS drives)
Enable-BitLocker -MountPoint "C:" -EncryptionMethod XtsAes256 -TpmProtector

# Enable with TPM + PIN
$pin = ConvertTo-SecureString "123456" -AsPlainText -Force
Enable-BitLocker -MountPoint "C:" -EncryptionMethod XtsAes256 -TpmAndPinProtector -Pin $pin

# Enable BitLocker on a data drive with password
Enable-BitLocker -MountPoint "D:" -EncryptionMethod XtsAes256 -PasswordProtector -Password (Read-Host -AsSecureString "Enter password")

# Add a recovery password protector (numerical recovery key)
Add-BitLockerKeyProtector -MountPoint "C:" -RecoveryPasswordProtector

REM manage-bde: enable with TPM
manage-bde -on C: -EncryptionMethod XtsAes256

REM manage-bde: enable with password (data drives)
manage-bde -on D: -EncryptionMethod XtsAes256 -Password

REM manage-bde: add recovery key protector
manage-bde -protectors -add C: -RecoveryPassword

Recovery Key Management

# View recovery keys
(Get-BitLockerVolume -MountPoint "C:").KeyProtector | Where-Object KeyProtectorType -eq 'RecoveryPassword'

# Back up recovery key to Active Directory
Backup-BitLockerKeyProtector -MountPoint "C:" -KeyProtectorId "{GUID-HERE}"

# Back up to file
(Get-BitLockerVolume -MountPoint "C:").KeyProtector |
    Where-Object KeyProtectorType -eq 'RecoveryPassword' |
    ForEach-Object { $_.RecoveryPassword | Out-File "\\server\share\BitLocker_$env:COMPUTERNAME.txt" }

REM manage-bde: view protectors
manage-bde -protectors -get C:

REM Unlock a drive with recovery password
manage-bde -unlock D: -RecoveryPassword 123456-123456-123456-123456-123456-123456-123456-123456

REM Unlock with recovery key file
manage-bde -unlock D: -RecoveryKey F:\RecoveryKey.bek

Disable / Suspend / Resume BitLocker

# Suspend protection (for maintenance, firmware updates, etc.)
Suspend-BitLocker -MountPoint "C:" -RebootCount 1   # Auto-resumes after 1 reboot

# Resume protection
Resume-BitLocker -MountPoint "C:"

# Disable BitLocker (decrypts the volume)
Disable-BitLocker -MountPoint "D:"

REM manage-bde equivalents
manage-bde -pause C:         &REM Pause encryption/decryption
manage-bde -resume C:        &REM Resume encryption/decryption
manage-bde -protectors -disable C:   &REM Suspend protection
manage-bde -protectors -enable C:    &REM Resume protection
manage-bde -off C:           &REM Decrypt and disable

Suspend Before BIOS Updates

Always run Suspend-BitLocker -MountPoint "C:" -RebootCount 1 before BIOS/UEFI firmware updates or boot configuration changes. Failure to suspend can trigger BitLocker recovery mode on next boot, requiring the recovery key.

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10. Best Practices

Monitoring Checklist

Run these checks regularly (weekly or via scheduled tasks):

# --- Comprehensive Disk Health Report ---

Write-Host "=== Physical Disk Health ===" -ForegroundColor Cyan
Get-PhysicalDisk | Format-Table DeviceId, FriendlyName, MediaType, HealthStatus, OperationalStatus, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}

Write-Host "`n=== Volume Free Space ===" -ForegroundColor Cyan
Get-Volume | Where-Object DriveLetter | Format-Table DriveLetter, FileSystemLabel, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}, @{N='FreeGB';E={[math]::Round($_.SizeRemaining/1GB,2)}}, @{N='Free%';E={[math]::Round(($_.SizeRemaining/$_.Size)*100,1)}}, HealthStatus

Write-Host "`n=== SMART Reliability ===" -ForegroundColor Cyan
Get-PhysicalDisk | Get-StorageReliabilityCounter |
    Select-Object DeviceId, Temperature, Wear, ReadErrorsTotal, WriteErrorsTotal, PowerOnHours |
    Format-Table

Write-Host "`n=== Recent Disk Errors (7 days) ===" -ForegroundColor Cyan
Get-WinEvent -FilterHashtable @{LogName='System'; ProviderName='disk','storahci','stornvme'; Level=1,2,3; StartTime=(Get-Date).AddDays(-7)} -ErrorAction SilentlyContinue |
    Format-Table TimeCreated, Id, LevelDisplayName, Message -Wrap

Disk Maintenance Schedule

Task	Frequency	Command / Tool
Check disk health	Weekly	Get-PhysicalDisk, Get-StorageReliabilityCounter
Review Event Viewer disk errors	Weekly	Event IDs 7, 9, 11, 51, 129, 153
SSD TRIM/Optimize	Automatic (weekly)	Scheduled task: "Optimize Drives"
Check free space	Daily (alert-based)	Get-Volume, monitoring agent
chkdsk scan	Monthly	chkdsk /scan or Repair-Volume -Scan
Firmware update check	Quarterly	Manufacturer tool / website
Backup verification	Monthly	Test restore from backup
BitLocker key backup	On change	Backup-BitLockerKeyProtector
Storage Spaces health	Weekly	Get-VirtualDisk, Get-StoragePool

When to Replace a Disk

Indicator	Action
SMART HealthStatus = Warning or Unhealthy	Replace immediately
Reallocated sector count growing	Plan replacement within days
Wear indicator approaching 100% (SSD)	Plan replacement
Recurring Event ID 7, 11, or 153	Investigate; likely replace
Read/write errors increasing	Replace proactively
PowerOnHours > 40,000 (HDD) or > 30,000 (SSD)	Monitor closely, plan replacement
Audible clicking or grinding (HDD)	Replace immediately, back up first
Multiple chkdsk repairs needed	Replace soon
Performance degradation not explained by workload	Investigate; may need replacement

Useful PowerShell One-Liners

# All disks, partitions, and volumes in one view
Get-Disk | ForEach-Object { $d=$_; Get-Partition -DiskNumber $d.Number -ErrorAction SilentlyContinue | ForEach-Object { [PSCustomObject]@{Disk=$d.Number; Model=$d.FriendlyName; Part=$_.PartitionNumber; Letter=$_.DriveLetter; SizeGB=[math]::Round($_.Size/1GB,2); Type=$_.Type} } } | Format-Table

# Find volumes with less than 10% free space
Get-Volume | Where-Object { $_.DriveLetter -and $_.Size -gt 0 -and ($_.SizeRemaining / $_.Size) -lt 0.10 } | Select-Object DriveLetter, @{N='Free%';E={[math]::Round(($_.SizeRemaining/$_.Size)*100,1)}}

# Export full disk report to CSV
Get-PhysicalDisk | Select-Object DeviceId, FriendlyName, MediaType, BusType, HealthStatus, OperationalStatus, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}, FirmwareVersion, SerialNumber | Export-Csv -Path "$env:USERPROFILE\Desktop\DiskReport.csv" -NoTypeInformation

# List all drives with their serial numbers and firmware
Get-CimInstance Win32_DiskDrive | Select-Object Index, Model, SerialNumber, FirmwareRevision, InterfaceType, @{N='SizeGB';E={[math]::Round($_.Size/1GB,2)}}

# Quick disk benchmark (simple sequential read test)
$testFile = "C:\diskspd_test.dat"; [System.IO.File]::WriteAllBytes($testFile, (New-Object byte[] 104857600)); $sw=[Diagnostics.Stopwatch]::StartNew(); [System.IO.File]::ReadAllBytes($testFile)|Out-Null; $sw.Stop(); Write-Host "Sequential read: $([math]::Round(100/$sw.Elapsed.TotalSeconds,0)) MB/s"; Remove-Item $testFile

# Identify which process has a file locked (requires handle.exe from Sysinternals)
# handle.exe "C:\path\to\locked\file"

# Monitor disk queue length in real time
while($true){ Get-Counter '\PhysicalDisk(_Total)\Current Disk Queue Length' | ForEach-Object { "$((Get-Date).ToString('HH:mm:ss')) Queue: $($_.CounterSamples[0].CookedValue)" }; Start-Sleep 2 }

# Generate disk health summary email-friendly output
Get-PhysicalDisk | ForEach-Object { $c = $_ | Get-StorageReliabilityCounter; "$($_.FriendlyName): Health=$($_.HealthStatus), Temp=$($c.Temperature)C, Wear=$($c.Wear)%, Hours=$($c.PowerOnHours)" }

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This reference covers Windows 10, Windows 11, and Windows Server 2016/2019/2022. Some features (Storage Spaces Direct, Storage Tiers, ReFS) are available only on Server editions. Always test commands in a non-production environment first.