Thanks to you all for your help. I am going to try the following (on the same lines as suggested by Olan):

1. Right now, the users log into a 'terminal' server, say abc, and run a shortcut to the application

2. The shortcut actually runs an application which is hosted on an application server, say xyz, on which the application build is hosted. The 'target' property of the shortcut reads something like '\\xyz\\appname.exe

3. Instead, I am going to just move the build to the 'terminal' server and host it from there instead of trying to access the build on \\xyz\.....

Hope this will eliminate most of the cases in which this issue occurs

The event log entry that you are seeing was not logged by PowerBuilder. That is your proof right there.

Thank you Roland. Is there a way to confirm this? I see this error in the event viewer at times -> "Windows cannot access the file  for one of the following reasons: there is a problem with the network connection, the disk that the file is stored on, or the storage drivers installed on this computer; or the disk is missing. Windows closed the program abc.exe because of this error"

I have placed a batch file which pings the network path from the terminal machine every 30 seconds in an infinite loop and log the output. Will this help identify if some pings fail, then maybe it has to be a network error?

Or is there a better way to prove it probably is a network error?

It is likely due to network issues causing the application to not be able to access a file it needs.