So its not a startup program...
Tried it safe mode?
go to settings/update & security/recovery
under advanced startup, click restart now button
this restarts PC in a blue menu
choose troubleshoot
choose advanced
choose startup options
click the restart button
choose a safe mode (it doesn't matter which) by using number associated with it.
Pc will restart and load safe mode
if it still happens in there it has to be some bizarre hardware problem.
If it works in safe mode, it has to be a driver of some sort.
Have you tried another mouse? Does mouse have its own software?