Hello Zach,
Thank you for your reply.
I am using Labview 32 bits in a Windows XP machine.
The TestStand calls are made through Labview VIs. I have developed these VIs from the examples that come with the VirtualBench installer. They are in fact very similar.
To verify the problem was related to VirtualBench I left the test sequence with a single call that sets the Power Supply in the Process Setup part of the sequence. If this call is made I get the error I mention at the end, if I skip this call no error.
Regards,
Raimon Pousa