While we're working on this suggested solutions are below plus try serial sync and removing hubs whenever possible. Soft reset the Pocket PC before putting it in the cradle to connect. DO NOT go through any down level USB hubs, even if they are powered. Disconnect all other USB devices, if possible. This only applies if you are having connectivity problems.
Many people use hubs and other USB devices and never have any problems.
Close out of the Connection Settings window, then reopen it. This is clumsy, but should reset wcesmgr.exe. Alternatively, you could use Task Manager to kill wcesmgr.exe and then manually launch ActiveSync from Programs or the Desktop before connecting. Watch Device Manager. Remove any ghosted USB devices in Safe Mode.