This is a bug I've discovered when using LabVIEW 6.1 in a multi-user Windows 2000 environment.
After underlying software changes and the like, it is common that when exiting a VI, a message pops up saying that an underlying VI has changed and must be saved. As a regular user, this cannot be done, because regular users don't have write access to the LabVIEW system folder.
When the same thing is done as Administrator, the changes can be saved. In this case, it was a change to a VI residing in the NI-DAQ ai.llb. After the save, the permissions on ai.llb (which by default included liberal access for the Users group) were changed to allow only access by the Administrators group, making it impossible for a regular user
to use that VI or any VI depending on it.
The solution is to manually edit the permissions on the .llb after the save to add the Users group back into the allowed users list.
