Windows black screen on login and Windows start menu not working

On our Windows 2012R2 and Windows 2016 RDS / Citrix servers, we had a strange issue. Users who were starting a new session could witness one (or all) of the following issues:

• The infamous black screen while logging in;
• Citrix WEM (Workspace Environment Manager) splash screen hanging on Citrix WEM processing filter conditions;
• The Windows start menu doesn’t work (right mouse click works).

This issue could act up within an hour or after a couple of days.

A look in the Event Viewer gave us two possible search directions:

• System: Timeout (120000 seconds) waiting for a transaction response from the AppReadiness service.
• Microsoft – Windows – AppXDeploymentServer/Operational: Errors with ID 404 and 801; stating the AppX deployment operation failed or that failed to open an AppX specific registry key.

Looking closely at the registry I saw that the following keys were missing:

1. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\AppReadiness
2. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Appx\AppxAllUserStore: within the AppxAllUserStore key we only had 1 key: InboxApplications. There were no other keys.

I exported these registry keys from a server with no issues and imported them into the failing server. I tested it with a user:

1. Logged on – fast, no issues;
2. Logged off;
3. Logged on – all the above issues occurred.

While performing the above actions I had Process Monitor running too, the registry keys were removed again by the Citrix User Profile Manager:

Googling this issue eventually led to the following discussion on the Citrix forum which led to this article. There is a private hotfix for this issue LC9648. In this article, Citrix states:

7.15 LTSR CU2 sessions might launch as a black screen. The issue occurs with sessions running on XenApp and XenDesktop 7.15 LTSR CU2 and 7.17 VDAs when Profile Management is enabled.

Workaround if you don’t have the hotfix

So if you have to wait for the hotfix and want to continue serving users in your environment there is a workaround. First let me say, I don’t think it’s the best workaround, but hey it solves the issues described in the blog post 🙂

I’m not sure what’s happens if there is an update for a Windows Store application (AppX) or you want to remove an application, so this workaround is at your own risk!

So let’s get to it now:

1. First of all, stop the Citrix User Profile Manager Service:
   1. Start Run (Windows Key + R);
   2. Press Services.msc;
   3. Press OK;
2. Import the AppReadiness and AppX\AppxAllUserStore registry keys;
3. Now go to the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\AppReadiness registry key:
   1. Click the right mouse button;
   2. Press Permissions;
   3. Press Advanced;
   4. Disable inheritance;
   5. Select the System account;
   6. Press Edit;
   7. Press Show advance permissions;
   8. Deselect Delete;
   9. Press OK;
   10. Select the Replace all child object permission entries with inheritable permission entries from this object check box;
   11. Press OK.
4. Now go to the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Appx\AppxAllUserStore registry key:
   1. Click the right mouse button;
   2. Press Permissions;
   3. Press Advanced;
   4. Disable inheritance;
   5. Select the System account;
   6. Press Edit;
   7. Press Show advance permissions;
   8. Deselect Delete;
   9. Press OK;
   10. Select the Replace all child object permission entries with inheritable permission entries from this object check box;
   11. Press OK.
5. Start Run (Windows Key + R);
6. Press Services.msc;
7. Press OK;
8. Start the Citrix User Profile Manager;
9. Restart the App Readiness service;
10. If the App Readiness service won’t stop, execute the following PowerShell script:

$ProcessOfAppReadiness = Get-CimInstance Win32_Process | Where-Object {$_.CommandLine -eq "C:\Windows\System32\svchost.exe -k AppReadiness"}
Stop-Process -Id $ProcessOfAppReadiness.ProcessId -Force -Verbose

So that’s is it for now!

Daniel Nikolic

Daniel Nikolic

Is interested in everything connected to technology. Has a passion for cloud, virtualization and software development. Always finds appropriate IT solutions for customers that match their needs strategically, technically and financially.

Core qualities
Quick thinker, result driven, ambitious, customer-friendly, enthusiastic

Hobbies
Running, listening to music, good food and doing fun things with family

Job description
CTO PepperByte, LoadGen, and BlueParq