The following does only take care of the “Plex” data.
You will have to back up your media files separately.
1)
Do you have a second hard drive in this computer?
Or perhaps at least a separate partition on the hard drive, which can be spared from the “big delete”?
If you do, follow this article to move the Plex data folder to the other drive: [HowTo] An extended guide on how to move the Plex data folder on Windows
2)
save the contents of the Plex branch of the Windows registry (Important. If you don’t, you’ll have to re-share your libraries to all shared users)
HKEY_CURRENT_USER\Software\Plex, Inc.\Plex Media Server
Export this branch into a .reg file (hint: right-click)
3)
unplug the hard drive with the plex data folder on it from the machine
Just a safety measure, to make double-sure that the Windows reset doesn’t mangle these data.
4)
perform the Windows reset
5)
re-attach your media storage. Make sure that each of the media files is available under the same Network address / drive letter / folder path / file name as before!
6)
import the .reg file (double-click) which was saved in step 2
7)
download and install Plex Media Server
8)
Reboot Windows
