>>>Hi All. I know that VFP9 runs under Windows 7 64 bit but must the user choose/set anything special like a compatibility mode or something for an AMD 64bit CPU ?
>>
>>My advice is don't go to 64 bit unless you have to. I ran into many more problems than I expected to. Who needs trouble from the OS? If there is a performance gain, which there is supposed to be with 6 GB of memory and up, I haven't noticed it.
>
>What problems?
>
>I find 64bit Win7 is fast and stable, and it allows a lot more RAM.
>
>All my development machines run it.

By definition it allows more RAM.

It broke two of my apps outright -- StrataFrame and Backup4All -- and required upgrades from others. And like I said, I have not noticed any performance gains. YMMV....