Microsoft offers steps to fix Storage Spaces parity problem on Windows 10

Microsoft is providing workaround steps to mitigate and recover files on devices using Storage Spaces with parity after upgrading to Windows Server and Windows 10 version 2004 (May 2020 Update).

The instructions appear after it’s been confirmed that the feature that supposed to protect your data stops working following the update, and it can cause data loss in many cases. According to the company, only storage with parity has been affected. The mirror and simple Storage Spaces are not affected by the issue.

Storage Spaces is a feature that allows you to group multiple drives into pools, which you can then use to create storage spaces with different types of RAID-like technologies, such as mirror and parity, to help protect your data from drive failures, and expand storage over time.

If you have been affected by the issues, Microsoft has published steps to use the troubleshooter settings and PowerShell to mitigate the problem, and the company also provides the steps to recover files if you still have access to the storage.

In this guide, you’ll learn the steps recommended by Microsoft to mitigate and recover files from Storage Spaces in a parity configuration after upgrading to Windows Server or Windows 10 version 2004.

• Storage Spaces workaround with troubleshooter
• Storage Spaces workaround with PowerShell
• Storage Spaces workaround with file recovery

Storage Spaces workaround with troubleshooter

The company has made available some automated troubleshooters to address some of the issues and mitigate the problem for some scenarios.

To check if the automated troubleshooter has run and applied the mitigation, use the steps:

1. Open Settings.

2. Click on Update & Security.

3. Click on Troubleshoot.

4. Under the “Recommended troubleshooting” section, click the View history option.

5. If the troubleshooter has attempted to run, you will see a critical troubleshooter or recommended troubleshooter with the title and description.

   • Hardware and devices troubleshooter: Automatically change system settings to fix a problem on your device. Explanation: This troubleshooter will prevent issues with the data on your Storage Spaces. After the troubleshooter has run, you will not be able to write to your Storage Spaces.
   • Storage space troubleshooter: Data corruption was detected on your parity storage space. This troubleshooter takes actions to prevent further corruption. It also restores write access if the space was previously marked read-only. For more information and recommended actions please see the link below. Explanation: This troubleshooter will mitigate the issue for some users and will restore read and write access to your Parity Storage Spaces. Files that have already had issues may need to be recovered manually.

Once you complete the steps, you’ll have an understanding if the problem has been mitigated. Microsoft also says that currently no full mitigation for all scenarios of this issue.

Storage Spaces workaround with PowerShell

To mitigate the Storage Spaces problem on Windows 10 or Windows Server with PowerShell, use these steps:

1. Open Start.

2. Search for PowerShell, right-click the top result, and select the Run as administrator option.

3. Type the following command to mitigate the parity issue with Storage Spaces and press Enter:

   Get-VirtualDisk | ? ResiliencySettingName -eq Parity | Get-Disk | Set-Disk -IsReadOnly $true

After you complete the steps, tour Storage Spaces should now be set to read only, meaning you will not be able to write to them. The device will still be usable, and any volume not seen as RAW should be readable.

The above steps are the equivalent to the troubleshooter above titled “Hardware and devices troubleshooter.” There is currently no manual equivalent to the troubleshooter titled “Storage space troubleshooter.”

Storage Spaces workaround with file recovery

If you are able to access your parity Storage Spaces, and it doesn’t appear as RAW in Disk Manager, you can attempt recovery using Windows File Recovery (WinFR).

To recover files from Storage Spaces, use these steps:

1. Open Microsoft Store.

2. Download the Windows File Recovery app.

3. Open the WinFR app.

4. Run segment mode (/r) with the undeleted files flag (/u) to recover files from your NTFS volumes. By default, this will recover all possible files. You can add filter flags if you are only interested in certain file formats (such as /n *.docx) and to reduce system file recovery. Example command to recover all docx files present in the C: drive to the D:\SpacesRecovery folder: winfr.exe C: D:\SpacesRecovery /r /u /n*.docx 

Once you complete the steps, you can view the recovered files. In the above example, you would need to go to D:\SpacesRecovery to see your recovered data. (You can learn more about the Windows File Recovery app in this guide.)

If you have a ReFS volume that shows as RAW in Disk Manager, you can use the refsutil salvage command to recover data to a volume of equivalent size. There are two options for salvage command: quick and full. A quick recovery may not recover as much data as a full recovery.

To perform a quick recovery, use these steps:

1. Open Start.

2. Search for Command Prompt, right-click the top result, and select the Run as administrator option.

3. Type the following command to recover files and press Enter:

   refsutil salvage -QA SOURCE-VOLUME WORKING-DIRECTOR DESTINATION-FOLDER

   For example:

   refsutil salvage -QA E: F:\SalvagedFiles

To perform a full recovery, use these steps:

1. Open Start.

2. Search for Command Prompt, right-click the top result, and select the Run as administrator option.

3. Type the following command to recover files and press Enter: refsutil salvage -FA SOURCE-VOLUME WORKING-DIRECTOR DESTINATION-FOLDER For example: refsutil salvage -FA E: F:\SalvagedFiles

   refsutil salvage -FA SOURCE-VOLUME WORKING-DIRECTOR DESTINATION-FOLDER

   For example:

   refsutil salvage -FA E: F:\SalvagedFiles

After you complete the steps, the files will be recovered in the folder you specified.