Hello, for starters: I'm really not sure how these problems started. It probably happened after one of many BSoDs that I had over the last couple of days.
My problem now, practically, is that I can't open an Explorer window. The desktop and taskbar work, and the process is running in the task manager, but whenever I try to open a folder or just bring up an Explorer window in any way, the process stops, my taskbar & desktop blink and explorer.exe starts right up but no window is opened.
The reliability monitor says that UIRibbon.dll is at fault, which kind of makes sense since I can still use the file choosing pop-up you get when you upload something through a website or when you're selecting a directory to save to, 'cause the ribbon isn't present in those windows.
What also happened when I first encountered the explorer-can't-open problem is that I've been logged out of some Windows programs, for example Steam, Origin and OneDrive. Not Skype, though.
I later found out that creating another account (I tried a non-admin local one) makes explorer launchable, although only on that account.
If I set my primary account to non-admin, the problem persists, but the Event Viewer lists less errors, I think. The ones I get as an admin are ID 10005, 7001, 10010, 10016.
Safe mode doesn't help, but states that an app (that might be called "Welcome" or something like that, I'm not sure because my language isn't set to English but I can check if it's important) can't be opened using the built-in administrator whenever I try to start up an Explorer window. It also said the same thing when I wanted to enter the Settings app, but it did open after I closed the error message.
SFC and DISM found nothing. CHKDSK "fixed" something but nothing changed. GPSvc couldn't be started via Services so I found instructions on the web to enable it through the regedit, but it didn't help.
Windows has brilliantly defaulted the System Restore Points to disabled so I have nowhere to go back to.
In-place upgrade (which was basically supposed to reinstall system files) didn't help. I had it set to keep my applications/programs.
No viruses or malware found with Avast and MalwareBytes, that was my first guess.
What strikes me the most is the fact that the newly-created account works just fine, it gives me hope that I won't have to do a clean install of Windows to fix this.
Any ideas what to do?
I'm not sure what logs to post here, there seems to be a lot of it.