OK Did you go the Logitech site to see if there was un updated driver for? Did you go to their site and look for support? Have you altered the position of the receiver? If to near the Monitor it could be getting interference from it. http://www.logitech.com How many USB devices do you have running a the same time? If you have several, Disconnect all except the mouse it could be running out of power. Try deleting the Port. Then re-boot your Machine and it will get recreated again. Try Microsoft's knowledge base http://support.microsoft.com Thanks, Barry, but it's not the mice. They both work fine if I connect them to a USB port. So it has to be the adaptor, the mouse port or some internal issue I would think. I'm using the regular (not cordless) mouse right now and it's OK. I'm just curious what the underlying problem could be. For a web-based membership management utility and information on list policies, please see http://nibec.com/24hoursupport/ To unsubscribe, send a blank email to 24hoursupport-request@xxxxxxxxxxxxx with "unsubscribe" (without quotes) in the subject.