MOUSE NOT WORKING AT ALL

Shut down the computer. Unplug the mouse and plug it back in. Restart the computer.
Right-click the "My Computer" icon your Desktop. In the menu that appears choose "Properties". Look in the "Device Manager" for "Mouse". (XP - open Device Manager by hitting the Windows key - the one with the win flag on it - and the Break key together) If there is a yellow exclamation point beside it you will probably have to re-install the mouse driver.

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