At this stage, you should check to see you're running the
latest ROM (A12). If not, go ahead, download it and install it. Note that it will nuke the contents of your PDA, so backup first. If you're cringing at the thought of a hard reset, I think one is in order, anyway. If everything on the device side is in top shape, try reinstalling Windows XP on your computer. Also, look at uninstalling ActiveSync completely, and then reinstalling it.