Sounds defective to me.
I have a a Microsoft Wireless Optical Desktop 1000 keyboard and mouse which connect to the PC through one USB port. My problem is that sometimes everything works fine, and then other times I switch on the PC and there are no lights on the receiver and I cannot use the mouse or keyboard. I have tested both a different mouse/keyboard on this PC and also tried the wireless keyboard and mouse on a seperate machine and both seem to work ok. Do I need to completely remove the drivers? If so, how? Any other ideas? Thanks for any help