Update 1803 destroyed OS and files. Need to do factory restore.

My computer is an old Gateway DX4860. It came with Windows 8.1 pre installed to partition 2 and backed up on part. 1 as a factory restore. This OS came with a free upgrade to Win 10, which I did as soon as I got it.
The latest MS update destroyed my OS on Part 2, including data and software, systemprofile (no desktop). It looks like the update reset my system clock a month ahead. That played havoc as files were trying to be rebuilt.
My system restore is gone. No control panel, no desktop, SFC is "unable to repair," neither RECOVERY nor Rollback work. And I do not have an image.

Resetting the BIOS to legacy and bypassing the Microsoft Boot Manger to boot directly from the HD I got it to boot to the Task viewer and from there browse the HD. Most of my file folders are there but the contents are empty. I did use wusa command to remove the update but that did not help.

With restore, recovery, and rollback not working, I assume, all I can do is activate partion 1 for a factory restore?

That, though, is the original Win 8.1. How will I get back to the free upgrade to Win 10? What do I need to do? (Lesson learned here is to always have a backup Image. Don't rely on restore, recovery, or rollback. )

In Windows 8.1, download the Windows 10 ISO file, mount it, and run setup.exe.

Download Windows 10

Hi - I am wondering if you ever found a resolution for this issue that brought you back your files? I am working on a same model Gateway DX4860 that is experiencing this same issue. It is not my own computer, but it is for my church. They told me it restarted for an update, and now won't boot. I have completed many of all the same troubleshooting you have mentioned. I was about ready to pull the documents off and rebuild, but looked in the various desktop/documents folders on the main user profile and there is NOTHING there. I am hoping that there is a backup from another person with the church that manages that. Before this we have had many problems with the DX4860 every time a Windows update would come down - but nothing this severe. Please let me know if you were able to resolve. Thank you,

Its a waste of time and effort doing a factory reset to 8 then to 10 as it may take any problems from 8 over. Create the dvd or usb boot fromit and do a clean install of 10 it will save hours of work