Bluetooth device not detected

Hi! I've got a problem with a USB bluetooth device not being detected
by Windows Me. The device is OK because I've tried with two different
devices. I think the USB port is OK too, because Windows detects it
correctly even after removing it from the device manager. Unfortunately
I can't be sure about this because I had no other USB devices on hand.
I checked and USB is enabled on the BIOS.

The problem is that I don't know Windows Me very well, where should I
look to find out the problem? Any suggestion on what can be the cause
of this problem?

Thanks in advance.