I've seen a few others asking about this same problem with LabVIEW 7 lately. As far as I've been able to figure, the VI has been corrupted. It acts like it's searching for a sub-vi with the same name as the top level VI, which you cannot do. The other posts I've read about this have not found a solution. I think you're stuck rebuilding it from scratch.
I think this may be an emerging bug in LabVIEW 7. Ed
