Solved users/settings on diffrent drive to os, problems reseting

Hi,
When I originally set up my PC with a clean install of windows 8.0, I installed the operating system on the C drive (my SSD) and users/settings on drive E (an HDD)
… it seemed like a good idea at the time.
When the windows 8.1 upgrade came out, I ran into an error due to my foolishness, and honestly, never tried to fix it.
More recently I have missed out on a few driver updates for my graphics card, and with windows 10 around the corner, it seems like the time to pull my finger out.
I have been trying to format, or reset, my PC with a fresh install of Windows so the users and settings are on the C drive with the operating system, so I can upgrade to 8.1. Each time I try through PC settings, or booting off my Windows 8 disk (64 bit OEM) Windows tells me it has failed, without giving any further information than that. There is no error message I can Google.
If anyone has come across something similar and knows a solution, I’d really appreciate a hand. If not I’ll have to take it into a repair shop at some point.
Thank you

Managed to find a fix.
I fully formatted E through windows explorer. This left a windows install with no user directory, so an empty blue task bar at the bottom of a black screen. I then booted off the dvd and reinstalled Windows. On Windows 8.1 now, and it all seems to be working properly.