"Windows cannot load the user's profile but has logged you on with the default profile for the system. " errors.
I reboot and now my desktop has completely changed, what ever changes I make and reboot the changes are gone and I am back to the default new user desktop.
It took me 2 hours of screwing around but I finally got my admin profile working again.
Regedit : HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList
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The pic above is my correct version, but what had happened is a virus or malware had changed my admin 500 profile into c:\users\temp so every time I logged in I was getting the temp users profile.
So what you need to do is change it in regedit. Just rename 1 to .bak and the good one to 500.
You will work it out :) Or leave me a message if you need help.