PSA for all those switching from Windows 10 to 11...There are definite issues with the upgrade that MS is very well aware of. However, they are kind of washing their hands in it by stating its usually caused by 3rd party drivers - example being wireless mouse driver, etc.
My cursor went bananas and was bouncing all around, sometimes even double cursors appeared. It was very difficult to control and even caused several files to open up, and more.
After attempting to shut down my touch pad and touch screen to eliminate any other possible way the cursor could move beyond the mouse - I finally shut off the human interface by disabling it and that brought my cursor under control again.
I highly recommend that if you do this update, you first back up your system and temporarily disconnect your wireless mouse and during update only use a wired mouse.
This whole upgrade took several hours to complete from backup to upgrade to fixing the issue caused by the upgrade.
I was not a happy camper, but I am now seeing better results, with one exception and that is I have noticed a bit of slowdown in response time. I think Windows 11 might be a memory hog.