file checkout/Locked for editing prohibits saving

Alright, heres whats going on. Once upon a time i had a win 2000 server with a domain. I regularly checked out files to update them and publish them to the web server under my user account for that domain. I then upgraded to win 2003 server with a different domain, so now all the filesi regualarly used are locked and i cannot save them in frontpage. This is due to the fact that a different user in a different domain (my old domain) has them locked, but that domain and that user are gone. I can get around saving them by saving the pages as somethign else and then renaming the file in windows explorer so i can still update the files it just takes a lot longer than it should. I want to know if there is any way that i can turn off the check out files option? How can i reset the files to not be checked out? How do i get in the position to be able to save the files once again as i used to? thanks for your help.