How can a program detect that it is running on Citrix?

Question

I am creating a program, which may or may not run inside a Citrix instance. The program needs to detect this, because it needs to behave in a different way on Citrix. How can it be detected in a reliable way? So far, my best guess was to check whether the computer has a C-drive.

Answer 1

I assume you want to know whether your application runs in a XenApp (aka Presentation Server / Metaframe) session?

Checking for the existence of drive C: is not the right way to do it. Historically, the drives letters on Citrix terminal servers were often remapped, e.g. from C: to M:. But this is not "en vogue" any more.

Please see my earlier answer for the correct way to determine the session type.

If instead you want to determine if XenApp/Presentation Server is installed, look up the corresponding registry values as described in Citrix Knowledgebase article CTX107570.