ActiveSync 4.5 has been working as well as can be expected of it (works about 85% of the time) on my PC running XP for a number of years now. I have a USB-to-mini-USB cable plugged into a powered USB hub that I’ve used with a number of mostly HTC Pocket PCs and Smartphones during this time. However, for the past couple of days I have not been able to sync any Windows Mobile device via ActiveSync 4.5 if they are plugged into any USB hub (I’ve tried two completely different hubs). The devices do sync (sometimes anyway) if plugged directly into a USB port on the PC itself. The hubs work fine with other USB devices (mouse, printer, flash card reader, etc.). So, I’m pretty sure the hubs, their cables connected to the PC, and the power cords (both are powered hubs) are working.