I use the "back up and restore files" from the control tab. It starts backing
up to my external hard drive, but then I receive the error message:
catostrophic failure 0x8000FFFF. My Dell XPS has no trouble finding the HD. I
had to retore my OS in November, after only 4 months. Hence, the need to back
up regularly. Any help would be appreciated.

I also tried to "change the settings" and get an error message for the C
drive as well.