Thanks for your reply. The PC I am running the vi on is (obviously) powered up. If I power the remote device down, then I get this error. However, when I power the remote device back up, I am unable to resume communications. The only error I log is this one. There is no hardware nor software handshaking in this protocol.
In the cold light of day, I think that the problem is with my VI as I am using shift registers to remember the previous Error. I guess I need to come up with a schema for resetting the error.
I've attached my code for your comments.
Richard