I have found the following problem in the VFP6.0 [Visual Studio 6.0]:

Open the VFP 6.0. Now open VC++. Go back to VFP and click on 'Open' in the menu bar. It is inactive. 'CTRL+O' does not work either.
If you open a file by MODIFY COMMAND, the 'Save' feature has the same problem.

Please try it and let me know.

Thanks,

Desh