Try connecting it to a powered hub, or make sure it's got its recharger connected.

@ Steve: I installed the drivers, even though they should not be needed, with no result
;)

Did you install the drivers for the MP3 player before trying to connect the device to the USB port?

Steve

Sounds like the player is defective.

@ ejn63: the player works Ok and can be connected in two different pcs under the same circumstances.. IMO it's a software problem

Thanks

I connected the iRiver to the power supply but it didn't work either. It doesn't seem to be a power issue

Thanks