Hello Community,



I have the weirdest Issue... My PC is used by my wife and me, each having our own Windows Account.



Some time ago we started experiencing an issue at startup of the system.



Good Scenario: (only one user involved)



1. User A is logged in and shuts PC down

2. PC boots up to login screen showing last user A login screen

3. User A logs in after booting, Desktop is shown after 2 seconds and programs load pretty fast

All fine!



Broken Scenario:



1. User A is logged in and shuts PC down

2. PC boots up to login screen showing last user A login screen

3. User B changing to his user in the login screen (bottom left user list) and enters his credentials and logs in

4. The loading phase takes really long, and when the desktop finally comes on, there are no buttons on the taskbar and the taskbar does not react on mouse clicks on windows icon or anything. The taskbar actually starts flickering when you try to click it.

5. only way to "solve" it is to CTRL+ALT+DEL and Reboot, as this will bring you back to Login Screen with last "User B", then User B can normally login (see good scenario above).



I tried googling that (pretty hard to search for) issue but found nothing. Eventually, for other reasons, I freshly installed Windows 10, but the issue again appeared on the same day I set the system up.



Same behaviour when Windows+L lock my screen and trying to login with a different User.



So the bottom line seems to be: when a user different from the one who was last logged in tries to start the computer it somehow takes a wrong turn and breaks the explorer.exe. (getting an explorer.exe Error in system logs)



I did some research and found out stems from my Razer Naga Pro Mouse.



As soon as I unattached the mouse (neither BT Dongle nor direkt connection) the issue disappeared and Startup was all fine.



As soon as I reattached the Mouse (either with BT Dongle or directly, and also tried different USB ports) the problem reappeared.



How can this be? And can this be fixed? Please advise!



Thanks!