Comodo Backup - error 100021

I have just downloaded Backup and completed the settings form to begin a backup when at the end of the procedure (before it even started a backup) it stated that the backup failed with Error 100021. I cannot find any trace of such a code and would appreciate your advice please.
OS - Win XP
Destination: ext HDD

im very confused as to what you are talking about. the settings “form” or settings tab so to speak contains no options to backup at the end of the procedure. the only thing that even sounds like what your doing is trying to run an additional backup after a backup is completed??? Are the settings you refer to the ones located in step 4 of the backup process?

Maybe you can help us understand what you are trying to do so that we can help you achieve this.

I’m having the same problem… see the attached file with screen shots.

[attachment deleted by admin]

After my last post, I tried Unchecking the “Track 0 and MBR” option in step 1 and the backup seems to be working. The drive E: is just a slave drive without windows installed on it. I guess track 0 or the MBR is empty, not used or is missing on this drive.