I have just had a strange problem, when an individual user tried to launch any published application another server desktop session was initiated with the below message, resetting the users profiles etc made no difference.
ICA Seamless Host Agent You have started Windows Explorer in your ICA Seamless session. This will obscure your local Explorer desktop. To re-enable this ICA Seamless connection, please logoff and restart the seamless remote application.
It turned out the cause of the problem was on the “Environment tab” for the users AD account the option “Start the following program at logon” was ticked, even though there was no program specified it was enough to stop the published application loading as it should.
Un-ticking the option instantly fixed the problem 🙂