I have a Dimension E520 running Windows XP. When I switch it on it boots up correctly but there is no response from the keyboard and mouse. I have taken all usb devices expect keyboard and mouse away and still they don't work. Tried in all usb points, tried new mouse still don't work. Please help!
Does the keyboard respond before Windows loads? If so, boot into Safe Mode (press F8 before Windows begins to load).
Do they work there? If so, you have a driver or Windows problem.