Assuming the last backup was performed before these problems began, I would not delete it as you may need to use it in order to resolve the current issue without reformatting and starting over. Even in the best case, it's a backup of your files you should not surrender until you have another recent backup of those files.
Since HP's maintenance program identified file corruption, I would start by running System File Checker per these instructions. You'll want to have your Windows 7 DVD ready in case it is requested. In addition, I would verify that the external hard drive has sufficient room for another full backup and try using a different backup media to see if it is the utility or the hard drive that is the issue.
Note: This post was edited by forum moderator to correct broken link on 10/29/2010 on 2:32 PM PT
On my new Compaq laptop with Windows 7 I was able to do auto backups on a regular basis. Now all of a sudden it will not do a complete backup. My backups were going to an external Iomega hard drive. At one point using the HP maintenance program it did tell me I had some corrupted files on the C drive. I have tried using restore to correct the corrupted file problem and it isn't letting go back that far to try and correct the problem. If I try to run a backup my external drive looks like it is receiving some files and then it just spins forever and I can't eject it. I was wondering would it be wise for me to delete the existing backup on my external drive & then try a new backup? HELP