The Windows mouse pointer randomly decides where it wants to be on any screen. Installing a new Logitech mouse with the latest drivers has not resolved the issue. The computer is running Windows XP.

Since you have installed a brand new mouse and the latest drivers, we can rule out the mouse itself being faulty. Therefore, the problem could either be hardware on the computer or something wrong with Windows. We will first have a look at the computer hardware. If the mouse is a USB mouse, try plugging the mouse into a different USB port on the computer. Should that resolve the problem, it seems there is a faulty USB port on the computer. However, should the problem continue it is most likely there is something wrong with Windows. The first possible problem with Windows could be something running in the background that is conflicting with the mouse. To test this theory, restart Windows into Safe Mode. This will only load the most essential processes to get Windows running. To do this, restart Windows and just before the Windows splash (logo) screen appears start tapping the F8 key. In the Windows startup menu that appears, select ‘Safe Mode’ and press ENTER. Once Windows has finished loading, check whether the problem persists. If not, it seems that something is running in the background causing the conflict. In this case, restart Windows (to boot back into Normal) mode, and then press CTRL-ALT-DEL to show the Windows task manager. Sort the processes by your User Name by clicking the ‘User Name’ column (if this column is not visible, go to the ‘View’ menu > ‘Select Columns’ and tick ‘User Name’). Then, begin to sequentially close processes until the problem stops. At this stage, you will know which process is causing the problem.

However, should the problem still continue in Safe Mode, my best advice would be to back-up all your data and attempt to reinstall Windows. Please let me know how this goes, as it would be interesting to hear whether you are able to resolve this issue.