Windows XP - administrative login

[bronchee2862]

I recently purchased some older computers at a local auction. The computers were upgraded to Windows XP Professional prior to being sold. I need to know is there any way that I can bypass the administration logon screen so that I can have access to the computer? I attempted to use the ctrl + alt + delete - twice, but it did not work. Since I don't know what the administrative password is, will I have to wipe the hard drive and install a new operating system?

 

[kimsland]

Ophcrack will do that
http://sourceforge.net/project/showfiles.php?group_id=133599&package_id=167699
Download the ISO, create the CD
And boot from it
It'll automatically find your Admin (and all of them) passwords

 

[bronchee2862]

Windows XP - admin login

Thanks, this definitely worked.