>>I don't think there is any specific version of VFP information stored in the .FXP. There is in the .EXE, but not the .FXP.
>
>There has to be something because if I try and run a VFP 8 fxp in VFP 5, with out the source so it compile on the fly, I get "Object file "myprog.fxp" was compiled in a previous version of FoxPro (Error 1195)"
>I'm sure I would have to open the file with low level handle and read a specific byte but was hoping someone already had found out.

This may not be the definitive answer but here goes... I just tried compiling a "Hello world" program in FPW 2.5 and VFP 6. In this case the first three bytes were the same but the fourth byte in the 2.5 version was "0xFF" (hex) and in the 6 version it was "0x20".

For the most part the bytes are the same with the 6.0 version adding several bytes (mostly zeroes) but missing one byte that the 2.5 version had.

I don't know if this helps but maybe you can check the same way for VFP 7 and 8 (I don't have these versions).