Bluetooth Mouse Moves Erratically - How Do i Fix It?

There can be a number of simple reasons why it moves. There are some old annoyance type programs that can be installed to make the mouse cursor move on its own, to keep the system active, could be a defective device, could be the surface you are using the device on, is causing the device to get a cycling reflection of the "laser" that it uses to check for movement of the device.

Normal troubleshooting is to try the problematic device on another computer to see if it exhibits the same behavior, along with using another pointing device to see if it is the computer that is the problem.