Sometimes when setting up a new host to be backed up you will end up seeing this error "Tar exited with error 65280 () status" when you attempt your first backup....
There are a number of things that can cause this but the most common I have found is that you have not yet accepted your remote hosts fingerprint/key!
SSH into your backuppc server either as your backuppc user or use su to get to that user. Then simply run ssh email@example.com
When prompted to accept your new hosts key just type "yes" and hit enter. Seems like 9 times out of 10 this will solve your problems!