Hello Dale,
Thank you for contacting National Instruments.
If you are already able to programmatically obtain the current user's login name for Windows, one solution is to compare the user name to a table of user names in LabVIEW when the VI is initially loaded. In this way, you can enable and disable controls using property nodes depending on the Windows login.
I have included an example VI that illustrates the basic idea.
I hope this helps! Let me know if you have further questions.
Matthew C
Applications Engineer
National Instruments