>I'm writing a VFP 3.0 app that will need to access and maintain free tables used by another application written in FoxPro 2.5 DOS. Structural compound indexes (.CDX) are used to order the records. Does anyone know of any compatibility problems that exist that would make this a bad idea? My big concern is whether or not VFP 3.0 and FoxPro 2.5 DOS update the CDX files the same.

Free table is compatible. The only thing you should remember: create/change table structure using Fox2x, else table will become unreadable for 2.x.