To fix a Windows mouse cursor glitch, first restart your PC, as temporary system bugs often cause cursor issues. Then check your mouse by unplugging and reconnecting it (or replacing batteries if wireless). Update or reinstall the mouse driver by going to Device Manager > Mice and other pointing devices, right-click your mouse, and select Update driver. You can also try changing pointer settings in Settings > Bluetooth & devices > Mouse > Additional mouse settings and disable pointer trails or enhance pointer precision. If the issue continues, run a system scan using sfc /scannow in Command Prompt or check for Windows updates to fix possible software conflicts.