OK, maybe this was really stupid. I had a 32GB flash drive formatted with the Win10 media upgrade image on it (bootable). I was going to use it to upgrade another system but in the meantime I wanted to copy some programs between two systems. I inserted the flash drive into my previously installed Windows 10 laptop which was running flawlessly for 5 weeks and setup using the D: user profile setup (autorun move of profiles to D post install step).
So now after I inserted the flash drive it appeared like my current windows 10 system was trying to reinstall windows 10 again, I didn't realize anything would happen simply by plugging in the flash drive. So I aborted the "getting windows ready" but now I can login to the system but have an error dialog:
C:\windows\system32\config\systemprofile\Desktop is unavailable. If the location is on this PC, make sure the device or drive is connected or the disc is inserted, and then try again. If the location is on a network, make sure you're connected to the network or Internet, and them try again. If the location still can't be found, it might be moved or deleted.
So when I open explorer and look in C:\Windows\system32\config\systemprofile I do not see a Desktop folder. I am guessing the install got to a certain point before I halted it and now some system files are gone. Damn I am so fuming over this, I assumed the flash drive insert would prompt before any action and I was just going to copy a couple of files to do an install of Visual Studio. I'm hoping there's a path to recovery that doesn't involve complete reinstall, there is a lot of additional software installed and configured now that I don't want to re-install! Hoping someone has some tips to try and recover this. I do have all the software on the system and can run it but I realize the OS is not fully configured.