I recently bought a PC for my wife's mother, who is a retiree living in another city. She uses the PC solely for playing Bridge and Chess.
It was an i5 PC with 4Gb of memory and a 500Gb HDD running Windows 7 Pro 64-bit.
When I set it up for her at my house, to test everything was working, it performed perfectly.
Not long after she took it home and started using it, she encountered a problem with the mouse pointer moving in the the opposite direction to what she was doing with her hand on the mouse. For example, when she moved the mouse left, the pointer tracked right. Up was down, etc.
Is it possible that she may have hit some control keys by mistake that caused the mouse pointer to act in that manner? I've encountered something similar with video cards that show the image sideways or upside down if you press the Control + Arrow keys.
Perhaps it's something similar. It's not the mouse, as I got her to swap-out the mouse with a different one and it did the same thing.
Thanks you for you help in this matter.