You can try a boot to safe mode and see if it works in safe mode. That's a clue needed to work this.
Also, if you forgot to uninstall norton or such prior to the upgrade along with some other titles, you find troubles.
Been ultra frustrated the past few days, I upgraded to windows 10 the other day and had a plethora of problems, so I decided to roll back to windows 8.1 today and everything seemed to work fine. But now when I log in to my normal local windows 8.1 account, explorer doesn't load at all, which leads to no other startup program loading.
I can get task manager open and see that explorer.exe doesn't even start. There are however other processes there including Desktop Window Manager and Windows Logon Application, which would seem to imply that some things are working, but for some reason explorer just refuses to work.
I've tried to run explorer.exe by creating a new task in task manager, but that doesn't load it either; it doesn't even show up briefly in task manager. However, if I run explorer.exe with administrator privileges, it does actually start and my normal startup programs begin to launch when explorer runs. The problem is running explorer with administrative privileges creates other problems that prevents me from doing a lot of things within windows, and doing this action every time I sign in is not a solution in my opinion. In addition, when I restart explorer.exe in task manager, it closes the process but doesn't reopen it.
Prior to upgrading to windows 10 I had no issues like this, so it seems safe to assume that updating to windows 10 and then rolling back is causing it, though I'm not sure how to resolve it. It seems like some sort of user account problem maybe, considering that it doesn't seem to know how to log in correctly?
I would greatly, greatly appreciate any help I can get here, as I said these past few days have been beyond infuriating and this is just icing on the cake. Thank you.

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