When moving to VFP 9.0 from a previous version, start by checking What's New in Visual FoxPro section of the VFP7, VFP8 and VFP9 help, in particular Behavior Changes Since ...
What's New in Visual FoxPro
The things to pay attention to
- Online Book What's New in Nine: Visual FoxPro's Latest Hits
- CoDe Magazine VFP 8.0 and VFP 9.0 Focus Issues