Win XP SP3.
I encountered a problem due to low disk space.
While logging onto my work computer via VPN, I got an error message that my user profile could not be loaded, due to insufficient disk space, and that the default profile would be loaded instead. The computer seemed to lock up while the default profile was being loaded. So I had someone turn the computer off and back on, and cleared up some space on the c: drive via the VPN connection. When I logged in again, it still seemed to be opening the default profile (with the Windows default color scheme instead of my personalized colors, and missing my other personalized settings).
I cleared up even more space on the c: drive, and tried logging back in several times, but still kept getting the default colors and settings.
I finally was able to get my original profile and settings back by doing the following.
The user profile folders are stored under C:\Documents and Settings\.
There were several folders there. (To avoid divulging my actual login ID, let's pretend my logon id was aaaabbbb and my logon domain was cccc.)
Under C:\Documents and Settings\ were the following folders, as well as some others which were not relevant.
I determined that the "aaaabbbb" folder appeared to be the one with all my personalized settings. Renaming the aaaabbbb.cccc.* folders and then logging in to the computer resulted in a new aaaabbbb.cccc folder being created, and the default settings still being shown.
So then I again renamed the aaaabbbb.cccc folder to something else, and renamed the "aaaabbbb" folder to "aaaabbbb.cccc", and logged back on.
This time my personalized colors and settings were shown.
I don't know if this was a good way of fixing the problem, but at least it worked.