And can't figure out what the issue is yet. Yes, it's one of the annoying Microsoft things about when updates are installed, long random file/folder names can happen. But your post worries me.
Are you trying to run with no backup or scissors?
I recently upgraded to M$ Win10 on my desktop, and have not had any issues accessing my user files contained on my 2TB external Seagate Backup Plus Portable Hard Drive (model SRD00F1) from either Win10, or Win8.1 which is on my Toshiba Satellite A215-S7425 laptop.
My user files are in two separate partitions - G, which is named Documents, with 299GB free space, and F, which is named Pictures, and has 440GB free space.
Documents contains a parent folder called Documents, with multiple child folders containing all my files which are not photos.
Pictures contains two parent folders called My Pictures, and My Documents. The My Documents folder contains a folder containing all my Outlook 2007 PST's. I have multiple child folders within the My Pictures parent folder.
The Pictures partition now contains a folder named 'fe86b6b666b2d573d83b0e5e661080', which from my laptop, is an empty folder. I'm currently not at home, so I'm not sure if I have access to it from the Win10 desktop machine. I do remember seeing it, but did not try to access it, as I feared it was a corrupt version of my pictures folder, as I'm now unable to see or access the F:\Pictures\My Pictures folder from the Win10 desktop. I have no problem seeing or accessing anything in the My Documents folder, nor do I have any problem seeing the F:\Pictures\My Documents\Outlook folder. I didn't open Outlook, as I didn't want to write to the drive. And honestly, I'm worried about even connecting the drive to the Win10 machine, for fear of not being able to gain access to ANY of my user files.
As a self-employed, small business, nature/landscape/macro photographer, not being able to access my images from my much faster desktop machine, is a VERY BIG PROBLEM!
Anyone have any ideas, suggestions, etc? I've tried to web-search the issue, but I'm not finding anything useful.
And the only resources I'm finding for setting file permissions back to default, are for system files and folders. I could not find anything on user files.

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