There are number of threads on this error.
They all happen when you try to open in LabVIEW 6.1 a VI, that has some tab controls on its front panel, and that was developed in the student or evaluation edition version 6i.
If you send me the VI that causes the error, I may be able to recover it. You can either post it here, or send it to support@ni.com
Zvezdana S.
National Instruments
