Visa error 0xBFFF00A6 after session is idle for an extended time.

Question

Just switched development platforms from Windows XP/LabWindows 8.5/Test Stand 4.0 to Windows 7/LabWindows 2012/Test Stand 2012/NI Visa 5.3.  I'm posting this as a LabWindows question, but could be related to Test Stand.  I have a test sequence that consists of calls to a DLL written in LabWindows.  The test equipment is initialized in the Test Stand setup section, and closed in the cleanup section.  Near the end of my test stand sequence (before cleanup), the sequence stops to prompt the user for input.  If the prompt is left unanswered for perhaps 30 minutes, when finally answered, the software continues on; the Visa calls from the LabWindows DLL to the test equipment fail with error 0xbfff00a6 - the connection for the given session has been lost.  I have stepped into the DLL code and verified that the Visa handle did not change value.  If the session does not sit idle for long (say less then 10-20 minutes), I do nto get any errors.  The DLL is not unloaded until the squence file is closed.  This is software that has been run for years on our Windows XP platform.  Any ideas of the cause of the error?

Answer 1

Hello Pete_Bratko,
Does the DLL work when you call it within LabWindows? Another thing that occurs me, is that you can try to debug that DLL within TestStand. Maybe, it could give you a hint about what's going on in the DLL.
Carmen.