What he said. The auto generated name is either too long or contains some special character that it's pulling from the build.prop. I just name mine BLRY2.2 add a dash and hit "append date" - no more problems.You need to create a Folder Name for you Backup...
All my Backups goto the External SD...When you choose Backup...You'll see a Field which will ask you for a Name of your backup...
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