BB not recognized by host machine

Hi!

I have the problem that my BB.xM is not recognized by my host PC
(Windows XP). One thing to mention: If I unplugg the SD card and
connct via USB, in the device manager of win for s short time there is
the OMAP3630 listed in "other devices". But with the card in, not even
this is shown.

In another forum it wa srecommended to use the external power supply
and wait to connect via usb until the kerlen is booted. But this
didint work, either.

Anyones a clue?
Thx

Sven