Get-Partition & Win32_Volume does not return all volumes and partitions on a disk

Question

Get-Partition & Win32_Volume does not return all volumes and partitions on a disk

SaravanaKumar Dhamodaran 0

Problem
I am using Get-Partition command & Win32_Volume class to get the list of partition and volumes in the disk. However, these commands are not returning all the volumes and partitions even though the disk management show the disks and volumes are healthy.
It is not always the case, in one scenario get-partition is not listing and on other scenario win32_volume is not listing.

Let me know what the reliable way is to get the partition and volume details without missing.

4 answers

Your answer

Answer 1

I get same result as in Disk Management with for example :

Get-Disk | ForEach-Object {
    $disk = $_
    Get-Partition -DiskNumber $disk.Number | ForEach-Object {
        $partition = $_
        $volume = Get-Volume -Partition $partition -ErrorAction SilentlyContinue

        [PSCustomObject]@{
            DiskNumber      = $disk.Number
            DiskModel       = $disk.FriendlyName
            PartitionNumber = $partition.PartitionNumber
            PartitionType   = $partition.Type
            SizeGB          = [math]::Round($partition.Size/1GB,2)
            DriveLetter     = $volume.DriveLetter
            FileSystem      = $volume.FileSystem
            VolumeLabel     = $volume.FileSystemLabel
        }
    }
}

Answer 2

Jason Nguyen Tran 12,485 Independent Advisor

Hello SaravanaKumar Dhamodaran,

Just checking in to see if there’s any update on this issue. If the suggestions helped resolve it, I’d appreciate it if you could click accept the answer. And feel free to reply if you need any further assistance. Have a nice day!

Answer 3

Jason Nguyen Tran 12,485 Independent Advisor

Hello SaravanaKumar Dhamodaran,

I’m just following up to see if the issue has been resolved. Let me know if you need any additional information.

If this answer was helpful, I’d really appreciate it if you could click Accept Answer. 😊

SaravanaKumar Dhamodaran 0 Reputation points

2026-02-09T06:41:32.96+00:00

Still the above suggestion is not much of benefit since,
Get-Disk and CimInstance -Namespace root/Microsoft/Windows/Storage -ClassName MSFT_Disk provide disk information, returning all disk detail in our case with both cmdlet. To map it to a partition, we need Get-Partition, as soon as we use Get-Partition, due to missing partition information, we are not getting all partitions. Screenshot attached, disk 9 output missing

The join class Win32_LogicalDisk only has entry for drive letters and not for mount points
Jason Nguyen Tran 12,485 Reputation points Independent Advisor

2026-02-10T02:58:43.14+00:00
This behavior is expected because Get-Partition queries the partition table directly, but certain partitions (such as hidden, system-reserved, or unmounted ones) may not be exposed in the same way.

To retrieve a complete view, I recommend using the MSFT_DiskPartition and MSFT_Volume CIM classes directly via Get-CimInstance. These classes provide more granular details than Get-Partition and can enumerate partitions even when they lack drive letters or standard mount paths. For example:

Get-CimInstance -Namespace root/Microsoft/Windows/Storage -ClassName MSFT_DiskPartition Get-CimInstance -Namespace root/Microsoft/Windows/Storage -ClassName MSFT_Volume

You can then join these results programmatically to correlate disk numbers, partition numbers, and access paths. This approach avoids the limitation of Win32_LogicalDisk, which only reports logical drives with assigned letters.

Another option is to query Win32_DiskPartition and Win32_Volume together, which can provide a broader view of partitions and volumes, though you may need to filter and normalize the output. Disk Management shows all partitions because it reads directly from the partition table, so combining CIM queries with PowerShell cmdlets is the closest equivalent programmatically.

You can try and please let me know how it goes. I'm happy to help further!

Answer 4

Jason Nguyen Tran 12,485 Independent Advisor

Hello SaravanaKumar Dhamodaran,

The behavior you’re seeing is expected in certain scenarios because Get-Partition queries the partition table directly, while Win32_Volume enumerates mounted volumes. As a result, hidden partitions, recovery partitions, or volumes without drive letters may not appear consistently across both methods. This explains why one command may list a partition while the other does not.

I recommend using the Get-Disk and Get-Volume cmdlets together, as they provide a more complete view of both physical partitions and logical volumes. Additionally, the MSFT_DiskPartition and MSFT_Volume CIM classes (accessible via Get-CimInstance) often return more accurate results than the legacy Win32 classes. If you need to capture every partition, including hidden or system-reserved ones, querying through Get-CimInstance -Namespace root/Microsoft/Windows/Storage is the most dependable method.

It’s also worth noting that Disk Management shows all partitions regardless of mount status, which is why it appears more comprehensive. By combining CIM queries with PowerShell cmdlets, you can achieve the same level of completeness programmatically.

I hope this clarifies the root cause and next steps. If you find this answer helpful, please consider clicking Accept Answer 😊 so I know your concern has been resolved.

Feel free to reply if you need any additional assistance.

Jason.

SaravanaKumar Dhamodaran 0 Reputation points

2026-02-05T14:20:51.67+00:00

Thanks Jason Nguyen Tran for your response. However still cannot get the partition details.

MSFT_DiskPartition: No class MSFT_DiskPartition, when using Get-CimInstance -Namespace root/Microsoft/Windows/Storage -ClassName MSFT_Partition, we are still not getting the missing partition, we cannot run Get-CimInstance -ClassName MSFT_Partition
Jason Nguyen Tran 12,485 Reputation points Independent Advisor

2026-02-05T16:05:28.0033333+00:00

The behavior you’re seeing is due to the fact that MSFT_Partition and related CIM classes only enumerate partitions that are visible to the Windows Storage Management API. Certain partitions, such as OEM recovery partitions, EFI system partitions, or vendor-specific diagnostic partitions, may not be exposed through these APIs, which is why they don’t appear in your queries. Disk Management, by contrast, shows all partitions regardless of mount status or visibility to the OS.

To reliably capture all partitions, including those hidden ones, I recommend using Get-Disk | Get-Partition in combination with Get-Volume, and supplementing this with Get-CimInstance -Namespace root/Microsoft/Windows/Storage -ClassName MSFT_Disk. The MSFT_Disk class provides metadata about the entire disk layout, which can help identify partitions that are not returned by MSFT_Partition.

If you still cannot see the missing partitions, the alternative is to query WMI directly using Win32_DiskDrive and Win32_DiskPartition, then join the results with Win32_LogicalDisk. While these legacy classes are less modern, they often expose partitions that the newer Storage namespace omits.

In short:

Use Get-Disk + Get-Partition for OS-visible partitions.

Use MSFT_Disk for full disk layout metadata.

Fall back to Win32_DiskDrive/Win32_DiskPartition if hidden partitions are required.

This layered approach should give you the most complete view programmatically.

You can try and feel free to ask if you need more information. Please consider clicking Accept Answer or Upvote the asnwer if you found something helpful.

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Get-Partition & Win32_Volume does not return all volumes and partitions on a disk

4 answers

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