Windows 2016 server VDA agent update from 2009 to 2112 application start problems

[Mika Jussilainen]

We have few Windows 2016 servers with VDA agent 2009 upgraded to 2112 and we have now very strange issues starting applications from workspace app and web interface. Problem is that application starts but in "lauching application" step it dissappears, usually it starts fine after waiting for some time. If user notices that starting application box disappears, he might click application again. We have limited so there can be only one application instance per user, but if user clicks on application icon several times, it sometimes opens two or three copies of same application. This should not be possible at all.

 

First it looked like old problems with timeouts so i checked that few registry settings are in place. Well those registry entries were missing after update, so i added them back but it didnt help. VDA's are not rebooted after changes but i think they should work without one.  Strange thing is that we have three machine catalogs updated to 2112 and only 2 of them are affected with this problem. Working one is for testing purposes but quite similar to not working production ones. This working one also does not have following registry entries, so i think they do not apply to this problem. Our delivery controllers are at version Citrix Xenapp 7.18. Workspace app is latests 2112.1, also tested with various older versions with same problems.

 

Here are registry setting added to VDA servers:

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Citrix\wfshell\TWI]
"ApplicationLaunchWaitTimeoutMS"=dword:000186a0
"LogoffCheckerStartupDelayInSeconds"=dword:00000010

[HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\Citrix Virtual Desktop Agent]
"DisableLogonUISuppression"=dword:00000000

[HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\Reconnect]
"DisableGPCalculation"=dword:00000001

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System]
"DelayedDesktopSwitchTimeout"=dword:00000001

[Björn Schläfli]

Hello Mike,

 

I've had a similar issue with sessions not launching or dis-and reconnect while launching. The reason for this issue have been Logitech webcams connected to the endpoint. Do your endpoints have webcams connected? Try to disconnect and test again.

 

The issue could be a change to webcam redirection in vda 2103 which can be set to legacy behavior by reg key

HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\HdxRealTime

Name: OfferH264ToApp

Typ: REG_DWORD

Wert: 0

 

I'm actually testing this key.

[Joe Robinson]

I've had a case open with Citrix with this issue since Jan. 11th.   

 

Server 2022, working fine with 2109.  Upgraded to 2122 and experienced the behavior you've described.  After rolling back to 2109, things still do not work --  complete with VDA cleanup.  

 

It's been  a rough few months of Windows Patches triggering "bugs" in other applications, so who knows whats going on.