Hello! 

We have a PowerBuilder program (2019 R3 Build 19.2.0.2728) that is having some random, unexplained issues in a VMWare Horizon hosted environment. The issue is that the end user can go about their normal workflows, and at random, their session locks up and they need to force log themselves out of Horizon and back in. The curious part is, when they log back in, they are able to continue on with their same session. So our program isn't crashing or locking up itself. This is happening across many, separate VMWare Horizon environments.

We have worked on this issue for some time with no success so far in finding root cause. Our logging indicates our software is not locking up itself, as our logs continue on as if nothing happened. 

One theory we have is that this could be related to printer calls Powerbuilder makes as you load DataWindows, which may be subsequently causing a lockup issue with Horizon. 

I was curious about some PB.INI settings we found related to Citrix, and if they could apply to our situation. 

This is the first one we are looking into trying. Does anyone have more information on exactly what this setting is doing? And whether or not it could help in another VM environment that is not Citrix?

This setting also caught our eye, and I have the same questions for it: 

If anyone has experienced a similar issue like this I am also open to any general advice or steps that could be tried further. 

Happy to provide additional info as needed.

Thank you!