While backing up some large AVI files to multiple DVDs using Backup MyPC, I got an error on the 9th disc:

Error: A defective or damaged area was detected on the media. The backup device failed to transfer the data.
Please check the following:
1. This media may be defective, it is recommended that you discard this media and try another

...etc.

I clicked the OK button and the backup stopped! I was expecting it to let me insert a new disc and continue the backup! Am I going to have to start over completely? Would I have been able to continue if I had inserted another blank disc before clicking the OK button? Is there a way to resume this backup or am I going to have to start over?

I found this check box in the advanced options: Enable CD/DVD failed backup recovery. The help says "When this option is selected you will be to resume a failed backup to CD or DVD discs from the point of failure without having to start over from the beginning." Of course this wasn't checked before I started. Does anyone know what happens if a media error happens with this option checked?

I'm guessing here but it sounds as if the program stopped at midpoint with no end of file marker due to a faulty disc.

If that is the case, then the disc will be unusable even with the data that is on it as the file will be incomplete and unreadable.

I think you're going to have to bite the bullet and redo it.

I would also ask, what brand of media are you using? Over the years I have few if any problems with media using Verbatim and TY. The only time I had any real trouble was a bad spindle of Fuji's. I believe they had just change suppliers. Needless to say, that was the last I used them.