Currently, I’m doing some Microsoft Azure image deployments for Windows 10 Multi-Session 22H2. During the automation part, I found an annoying bug that I want to share with you. This bug is so irritating that it will corrupt Windows after using the Install-Language module. You will notice that you can’t connect via TCP/IP to the system anymore (including RDP/Bastion). Redeployment of the operating system is needed since there is only access via the serial console.

Multiple people contacted me, facing the same issues since I tweeted about this issue. Tweet link: There is a workaround for this issue, which I will describe in this blog too.


When using the latest marketplace image for Windows 10 Multi Session 22H2:

#ARM Marketplace Image Info
os_type = "Windows"
image_publisher = "MicrosoftWindowsDesktop"
image_offer = "Windows-10"
image_sku = "win10-22h2-avd"

The operating system will fail after executing the following command:

Install-Language nl-NL -CopyToSettings

Or executing a similar command like:

Install-Language de-DE -CopyToSettings

After running the Install-Language command, the system will be inaccessible via TCP/IP when rebooting the machine. So, no access to the VM with RDP or Bastion. Via the serial console, I have figured out that the Windows Firewall service isn’t running and can’t be started. Something breaks the operating system when running the install-language command. Even my automated Packer build will fail with the weirdest filesystem error messages like:

==> azure-arm.DTJ-AVD-DEV-Win10MS: Attempting to perform the InitializeDefaultDrives operation on the 'FileSystem' provider failed.


I found a workaround like the old days: just reinstalling Windows NT4 SP6A every time. People who faced this issue confirmed this workaround works for them.

The workaround is as follows:

  1. Install-Language nl-NL -CopyToSettings
  3. Install Windows updates!
  4. Reboot machine

Installing a cumulative update after using the Install-Language seems to fix the issue or repair the operating system. So if you don’t have updates, or the marketplace image is up-to-date, then you’re screwed!

Use an alternative method to install language packs

At first, I liked the new PowerShell command Install-Language. The Install-Language command saves much time and complexity compared to the alternative method. Since Install-Language is breaking the operating system, I prefer to use the alternative method with DISM and LXP. I’ve written a blog in the past about this procedure:

Last words

I hope I’ve saved you some troubleshoot time by posting this information. The first time I ran into this issue, it took me hours to troubleshoot and identify it was Install-Language breaking the Windows 10 Multi Session operating system. Note: I didn’t verify if Windows 11 Multi Session has the same issues.

It would be nice if Microsoft will fix this issue in the next releases of Windows 10 Multi Session, so Install-Language will make our automation live easier.