A few of our XenApp 6 customers are seeing issue sometimes when users move from one workstation to another and try to connect to their running session. An error box pops up with "A device attached to the system is not functioning" This is on healthy 2008 R2 servers with all Citrix hotfixes applied.
After the error, the user's session must be logged out before they can get back in. This was posted here: http://forums.citrix.com/thread.jspa?threadID=273457 , but is not answered.
There is nothing telling in the event logs, and it is an inconsistent problem.
Has anyone else seen this issue of found a fix?