I'm using VFP 7.0

I'm currently having a problem with "set classlib to myBase.vcx in myLibraries.exe".
If I leave my Development directory alone, the exe runs fine, but if I rename my Development folder then the exe crashes "Cannot find myDevelopmentFolder\myBase.vcx".

Obviously the program is picking up the path to my Development version of myBase.vcx and using it.
How do you prevent an exe from using the Development version of files without renaming the Directory?

TIA