A variation of this was posted earlier but I couldn't fully understand the solution so I am asking again. When I logged into windows 7 earlier today it was looking rather different. The desktop theme had disappeared. The icons on start menu were gone. When I started firefox it was as if I was running for the first time. My Deluge (bit torrent client) was empty. Next I found there was nothing in the My Documents folder or My Videos folder.
I fixed the FF issue by manually copying the "old" profile to the new one that was created. I found that in documents library the properties referred to a "C:\Windows\System32\config\systemprofile\Documents" folder rather than the old C:\Users\myself\ folder.
So I know that my windows profile is corrupted and the prior post refers to this page http://www.nextofwindows.com/how-to-change-user-profile-default-location-in-windows-7/ but I don't follow what I need to change in the registry entry to fix this.