Well, since you have 5 posts, and all 5 are trying to say the same thing, here you go:
-Download the latest 7280 software from the Cingular web site. You want to download the Handheld OS software. BlackBerryOS 4.x Download FAQ - UPGRADE DOWNLOADS
- Execute the downloaded software
- Locate and delete VENDOR.XML on your C: drive
- Restart Desktop Manager with the BB connected to your PC
- The OS should now reload.