Citrix XenApp/Desktop app won’t load fully and disappears during launching

Symptoms or Error :

Published Applications or Desktops don’t launch, or disappear during launch. There are no errors presented to the user, Event Log of the XenApp server or VDA hosting the application reports the following “EventID:20499 – Remote Desktop Services took too long to load the user configuration from server servername.domain.com for the user XYZ”.

The issue can present 2 different symptoms:

  • The application appears to launch, loads up to 80% then immediately closes.
  • The user sees application starting notifications, and after that, the application is never actually launched.

Here are the additional troubleshooting steps.

  • Go to StoreFront and try to load the application from the StoreFront web host web URL, if the slowness is still there then it eliminates the possibility of any client-side network slowness issues posed between Netscalers and Studio.
  •  Go to Delivery Controllers and view the application status: If you see the session at the pre-login status and then it vanishes then that means that Session is successfully trying to load but something is not letting is keeping it from the successful load. Check Profile Manager, Folder Redirection configuration if any which could also contribute to such issues.
  • Also, check the XenApp/XenDesktop server to view the event log. If you see Remote Desktop took too long to load then it means your session is not getting enough time to load the app and it needs more time to successfully load profile/session before projecting to the client machines.

If you see any of the above issues then the following setting should fix the session load VDA end issues. You need to perform these changes on one VDA first, put the rest of the machine on the maintenance mode to test and verify the results. Taking a snapshot of the VDA is not a bad idea.

Solution:

WARNING! Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Citrix cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.
There are a couple registry values that can be tweaked to give the application more time to launch. For example, if you are publishing Explorer, then Explorer will not launch unless LogoffCheckerStartupDelayInSeconds is set to 10 seconds (hexadecimal) or higher.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Citrix\wfshell\TWI
Name: LogoffCheckerStartupDelayInSeconds
Type: REG_DWORD
Base: Hexadecimal Value
Data: <An integer for the length of time to wait for application start. – Enter the delay time in seconds, up to 10 minutes (600 seconds)>

Note: Start with 10 seconds and move up from there 10 seconds at a time if needed.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Citrix\wfshell\TWI
Name: ApplicationLaunchWaitTimeoutMS
Type: REG_DWORD
Base: Decimal Value
Data:<desired additional time-out, in milliseconds >

Note: Start with 100000 milliseconds (I choose 70K ms) and move up from there to 300000 milliseconds if needed.

Desktop VDAs have an additional registry value that can be tweaked. If a desktop VDA closes before the logon process completes, you can allocate more time to the process. The default for 7.6 and later versions is 180 seconds (the default for 7.0-7.5 is 90 seconds). On the VDA machine (or the master image used in a Machine Catalog), set the following registry value: