thank you Falko..
I was able to backup many times before but for some reason now, it will only show a download size of 211k file. The site is well over 100m (not sure if that has anything to do with it). This has happened in the past with other ispconfig installs/sites but nothing was really "Live" i.e. non-production but now this site is live. I've backed it up about 8 times in the past. Now..no go!