WMDC problems

I'm using a T-Mobile MDA Vario III using WMDC 6.1 on Vista Ultimate x64.

I don't connect frequently - last time I did was 31st March. It normally
works fine, but today when I connected it to sync some new maps onto it for
Co-Pilot Live 7, it does not connect. The Sync icon shows its not connected
and when I start the WMDC program it gets as far as showing the WMDC logo
where it says 'please wait while WMDC starts', and gets no further.
I've removed WMDC, rebooted and re-installed it, but that had no effect. I
can't find any details in the event log. I deleted the partnership from both
sides when for some reason WMDC started up (though it said the device was
disconnected).

I know it connects because I get the normal windows sounds upon device
connection and disconnection, and I see a network connection for it too.
Also, I use Pocket Controller which can connect to the phone over USB. Any
ideas what I can do to get it working?

Thanks
Mike