Vista will not Restore backup files from external HDD!!?

I have Vista Home Premium Edition installed in my system.  Recently, due to a problem with corrupted protected system files, I was forced to conduct a clean re-install of the operating system.  This was the only solution available, after much email correspondence with Microsoft Technical Support who had been unable to resolve the issue.  Before re-installing Vista, I backed up my files, pictures and music to an external hard drive.  After reinstallation I have attempted to restore the backup files, unfortunately Vista does not recognize the backup source.  When turning on the external drive my system recognizes it, however when navigating to Control Panel/System and Maintenance/Backup and Restore Center/Restore files from backup/and then to Restore Files I receive a yellow yield icon with an exclamation indicating that "There are no backups available on this computer".  Very odd.  I cannot seem to restore my files from the previous installation?  I checked the external HDD to insure that the files are stored, and they are there.  Can anyone help me with this problem?  Thank you in advance!