Why is sometimes the Caption of top level windows empty or missing when queried over ICAClient (WfIcaLib.dll)?

[Gerd Winkler]

We use a local installed dll (WfIcaLib.dll) to query the captions of all top level windows of the current Citrix session. We use that information to decide if the Skype for Business client is running or not. Our Process runs locally on the workstation of the user. Most of the time this approach works. But sometimes we don’t see a Skype for Business Client running in the top level windows even if it is clearly running on the users desktop. We don’t know if the entry is missing in the top level windows or if the caption is just empty. It is not a permanent problem for some users. We don’t see a pattern yet. Some users have the issue for half a day and then the problem disappears. This makes it very difficult for us to troubleshoot.

With the API we do the following:

-          Create ICAClient

-          Enumerate CCM Sessions

-          Iterate over all CCM Sessions

-          Get Session ID

-          Start Monitoring CCM Session

-          Get all top level windows of the session

-          Compare the caption of the window with “Skype for Business”

We could also share C# code if needed, the code for this query consists of approximately 40 lines.