First off, I had Acronis Os selector for about six months and using it to boot four hard drives (XP home, XP Professional, XP and another XP Professional). They have all worked great and never had a problem with the Os selector till tonight. Installed a new hard drive and my bios detected it as well as OS selector. I have one drive that is set up as my main drive and Acronis Os selector has its own partion on that drive also. Proceeded partitioning the new hard drive for Vista (500 G Western Digitial drive/Sata) with disk director suite and everything went fine. Created the new parition and rebooted the new pc with the Vista DVD. After Vista finished installing and required to reboot, it popped up with an error message and rebooted (couldn't get the message). Since Vista disabled booting with my other four drives, used my Acronis OS media builder disk and reactivated OS selector. It successfully activated, but each time I click on one of my XP installation I receive an error message for Acronis saying: "Error: Acronis OS Selector was unable to load XP file system Operating System: Error." Keep in mind all drives were working fifteen minutes before I started installing vista so not for sure how to repair the situation. Any help or advice will be appreciated (except the format and reinstall excuse) and please I don't want to have to go back installing everything again for all four drives.