Win 8.1 One/SkyDrive Folder Access Error

[+Zagadka Subscriber²]

Randomly today, I began getting this message from OneDrive (on Win 8.1):

 

"Files can't be uploaded because we can't access this folder."

C:\Users\<name>\SkyDrive\Documents\

 

I haven't changed jack on my system. At all. It just started popping up. I've gone and checked the access rights, everything is perfectly fine. I've logged in and out (with reboot) of my Outlook account. I can manually access everything, I can access OneDrive online in the browser and in the Win8 Modern App (though the latter pops up the "can't access files" error, It starts with "All files are up to date" then moves to "Folder access problems").

 

The only weird thing is that the system seems to regard SkyDrive and OneDrive as the same folder names, but it has always been that way without error.

 

Now it just keeps putting error icons in the system tray.

 

MS hasn't been much help, I've tried the things they recommend. So... help?