Merge pull request #823 from MicrosoftDocs/mattw-troubleshooting

Update vitualdisk troubleshooting solution

Author: mattwojo

WSL/install-win10.md

@@ -130,10 +130,18 @@ Below are related errors and suggested fixes. Refer to the [WSL troubleshooting
   - Please make sure that virtualization is enabled inside of your computer's BIOS. The instructions on how to do this will vary from computer to computer, and will most likely be under CPU related options.
 
 - **Error when trying to upgrade: `Invalid command line option: wsl --set-version Ubuntu 2`**
-  - Please make sure that you have the Windows Subsystem for Linux enabled, and that you're using Windows Build version 19041 or higher. To enable WSL run this command in a PowerShell prompt with admin privileges: `Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Windows-Subsystem-Linux`. You can find the full WSL install instructions [here](./install-win10.md).
+  - Enure that you have the Windows Subsystem for Linux enabled, and that you're using Windows Build version 19041 or higher. To enable WSL run this command in a PowerShell prompt with admin privileges: `Enable-WindowsOptionalFeature -Online -FeatureName Microsoft-Windows-Subsystem-Linux`.
 
 - **The requested operation could not be completed due to a virtual disk system limitation. Virtual hard disk files must be uncompressed and unencrypted and must not be sparse.**
-  - Please check [WSL GitHub thread #4103](https://github.com/microsoft/WSL/issues/4103) where this issue is being tracked for updated information.
+  - Deselect “Compress contents” (as well as “Encrypt contents” if that’s checked) by opening the profile folder for your Linux distribution. It should be located in a folder on your Windows file system, something like: `USERPROFILE%\AppData\Local\Packages\CanonicalGroupLimited...`
+  - In this Linux distro profile, there should be a LocalState folder. Right-click this folder to display a menu of options. Select Properties > Advanced and then ensure that the “Compress contents to save disk space” and “Encrypt contents to secure data” checkboxes are unselected (not checked). If you are asked whether to apply this to just to the current folder or to all subfolders and files, select “just this folder” because you are only clearing the compress flag. After this, the `wsl –set-version` command should work.
+
+![Screenshot of WSL distro property settings](media/troubleshooting-virtualdisk-compress.png)
+
+> [!NOTE]
+> In my case, the LocalState folder for my Ubuntu 18.04 distribution was located at C:\Users\<my-user-name>\AppData\Local\Packages\CanonicalGroupLimited.Ubuntu18.04onWindows_79rhkp1fndgsc
+>
+> Check [WSL Docs GitHub thread #4103](https://github.com/microsoft/WSL/issues/4103) where this issue is being tracked for updated information.
 
 - **The term 'wsl' is not recognized as the name of a cmdlet, function, script file, or operable program.**
   - Ensure that the [Windows Subsystem for Linux Optional Component is installed](./install-win10.md#enable-the-virtual-machine-platform-optional-component). Additionally, if you are using an ARM64 device and running this command from PowerShell, you will receive this error. Instead run `wsl.exe` from [PowerShell Core](https://docs.microsoft.com/powershell/scripting/install/installing-powershell-core-on-windows?view=powershell-6), or Command Prompt.