I too am unable to back up on-line...have talked twice to Intuit Support and the problem remains unresolved.  History...Had to replace computer (iMac) and have to run QB on a virtual machine with Windows using Parallels.  For over 20 years have been using VMware Fusion for the virtual machine with no problems, but IT suggested switching to Parallels.  Windows, Parallels and QB were all installed with latest updates.  After installation of all of the new software back-up worked fine for a couple of weeks and then stopped working.  Intuit Support suggested reinstalling QB which was done along with reinstallation of Parallels and Windows and back-up still fails.  There is communication as I do get the e-mails saying that back-up was unsuccessful.  I have also reconfigured the back-up and get to the point where it says "backing up data", but after it runs for awhile I get the data back-up unsuccessful popup and also citing error 1013.  Any ideas what the problem might be?  Thanks!