Need Some Help with Log on Loop

[Mjd0116]

   Okay Now I have 2 Windows XP Pro installed on my HD and it lets me log onto one but not the other, the other with all my old data still logs me in and right back out saying how it saves my settings but I can now get in there.

I'm still not sure If I want to format the HD though, I do need to remove 1 of the windows though, So far I'm going to copy and paste the good windows files into the bad see if that fixes the other OS before I format if I need to.

Also I used Product Key to see what the Windows key was and it doesnt match the one I have inside my PC, So it's probably not Valid How can I get it to match the one I have So I can get updates if I do have to format my HD?

and what would be the best way of removing one of the Windows XP Pros?

[Lisandro]

and what would be the best way of removing one of the Windows XP Pros?

Did you install the new one with a valid XP key? Why don't you just keep it?

[Mjd0116]

No the new ones key is not valid 

[Mjd0116]

I guess my best bet now is to format the HD I'll lose some applications but I think Half of them are missing their .exe files because of the Win32 vitro virus Avast cleaned up.

But As I said before I have my Old Windows XP Pro CD key from the inside of my PC case, When I install using my friends XP Pro disk and enter my key it says it is invalid and doesnt let me continue.