If you are the first time you start a computer, this problem is mostly because your PS/2 keyboard mouse is connected to the host after the host is started, so the host is unable to recognize the PS/2 keyboard mouse, the solution is to speak computer shutdown, keyboard mouse connection to the boot.
Note: The USB interface Keyboard Mouse does not exist this problem, just need to wait 10 seconds for the computer to recognize.
Second, the cleavage is not the first time, the mouse keyboard problem is mostly the mouse keyboard itself, change a mouse keyboard or computer to try.
Third, the elimination of the mouse keyboard itself, there may be a host to the mouse keyboard power supply is insufficient
It is recommended that you use a live Usbhub or a PS/2 adapter using a USB switch. It is also possible that Windows XP by default to open the power-saving mode, resulting in insufficient USB interface, so that the USB interface intermittent failure. Right-click My Computer/Properties/hardware/Device Manager, double-click the Universal serial Bus controller to several "USB Root Hub" to double-click on any one, open the Properties dialog box, switch to the Power Management tab, remove the "allow the computer to turn off this device to save power" before the check, click OK to return, Restart the computer after you have modified the properties of each USB Roothub in turn.