Dennis,
Look at the VFP8 help file on SET ENGINEBEHAVIOR, this change was made to make VFP SQL more ANSI compliant. You need an aggregate function to use GROUP BY.
>The following statement from my VFP6 code gets a "Group By clause is invalid" error in VFP8:
>
>SELECT * ;
>FROM rm!Vehicles ;
>GROUP BY Vehicles.Brand ;
>ORDER BY Vehicles.Brand ;
>INTO CURSOR myList1