Screen flickers after you install Server Core App Compatibility FOD in Windows Server 2019 Server Core

On a Windows Server 2019 Server Core-based computer, you install Windows Update and then you install Server Core App Compatibility Feature on Demand (FOD). After you restart the computer, the screen flickers.

To work around this issue, install FOD before you install any update from Windows Update. Or, use the DISM /offline method to install FOD.

After Cumulative Update KB 4469342 and Servicing Stack Update KB 4470788 are installed, this issue won't occur.

Note If the Server Core installation installs these updates directly from Windows Update, no additional actions are needed to avoid the issue. However, if you manually install these updates by downloading them from the Microsoft Update Catalog, you must install update KB 4470788 before any other updates or the App Compatibility FOD.

If you already encountered this issue, follow the steps below to recover the computer.

Remove App Compatibility FOD from a .vhd/.vhdx file (Hyper-V environments)

If the issue occurs on a virtual machine (VM), follow these steps to mount the .vhd or .vhdx file to another computer, and use the DISM command to remove FOD. To do this, follow these steps.

Important If your affected VM has checkpoints, revert to a checkpoint that was created before App Compatibility FOD was installed to fix the issue. Otherwise, you must merge your checkpoints to successfully mount the .vhd or .vhdx file.  Read and understand the user guide for managing checkpoints, and follow this procedure carefully.

1. Log on to the Hyper-V host as an administrator.
2. Shut down or turn off the Server Core VM by using  Hyper-V Manager.
3. In Hyper-V Manager, right-click the VM and select Settings.
4. From the Hardware menu on the left side of the Settings window, select Hard Drive.

5. On the right side of the Settings window, under "Media > Virtual hard disk," note the path and file name of the .vhd or .vhdx file, and then select Browse.
6. In the File Explorer window that opens, find the .vhd or .vhdx file that you noted in the path in the Settings window.
7. Right-click the .vhd or .vhdx file and select Mount to mount the file as a drive letter on the Hyper-V host.
8. Search cmd.exe in Start, right-click the command prompt in the search results, and then select Run as administrator.
9. From the command prompt, run this command:

   DISM /Image:<drive_letter>: /Remove-Capability /CapabilityName:ServerCore.AppCompatibility~~~~0.0.1.0
   

When the progress bar completes, App Compatibility FOD is removed.

10. Open File Explorer, right-click the mounted .vhd or .vhdx file, and then select Eject to unmount the file.
11. In Hyper-V Manager, start the VM to check whether the issue is fixed.
     

Use PowerShell remotely to remove App Compatibility FOD

To use PowerShell remotely to connect to the server, the system must meet the following requirements:

• Windows Remote Management (WinRM) is enabled on the server. By default, it's enabled for Server Core installation.
• A trust exists between computers to establish a remote session with the server.

Follow these steps:

1. Run the following command in PowerShell to create a remote session with the server:

   Enter-pssession -computername <computername> -Credential <username>
   

2. When the remote session is established, run the following command to remove the App Compatibility FOD:

   Remove-WindowsCapability -Name ServerCore.AppCompatibility~~~~0.0.1.0 -Online
   

3. Then, reboot the server:

   Shutdown /r

Remove App Compatibility FOD from a computer by using Windows Setup and Repair

To follow these steps, you must use a DVD or USB flash drive to start the computer to the Windows 10 or Windows Server setup experience. Then, follow these steps:

1. In the language and keyboard layout selection window, select Next.
   
   
    
2. In the next window, select Repair your computer.
   
   
    
3. On the Choose an option screen, select Troubleshoot.
   
   
    
4. On the Advanced options screen, select Command Prompt.
   
   
5. Determine the drive letter that the affected Server Core Windows is installed on, and then run the following command from the command prompt:

   DISM /Image:<drive_letter>: /Remove-Capability /CapabilityName:ServerCore.AppCompatibility~~~~0.0.1.0

6. After the command is completed, shut down the computer, remove the bootable media, and then start the computer normally.