I am looking seriously at moving from VFP 7 to VFP 9. In investigating the differences, I inadvertatly left a line of VFP 9 code in one of my classes-'Set reportbehavior to 90'. This vcx was subsequently compiled and tested in VFP 9. I was then distracted and had to remake the production app (without recompiling all) with this line still in it. About 11:30 that night I realized my error and fired up the computer to test to see what would happen if I printed a report. To my surprise, when the app was run and a report was printed there was no error! However, if I return to the VFP 7 development environment, recompile the vcx and run it I get an 'unrecognized' error. I thought, well this computer has VFP 9 on it so the exe must be seeing the 9 runtimes. I moved the app to a machine witout VFP 9 and got the same results.I really am perplexed by this behavior and I hope one of you advanced users out there can explain this kind of behavior.