Thanks for the precisions. I still can't figure out how you ended up with duplicity installed and deja-dup-backend-gvfs not installed, this should not have happened, judging from my understanding of the code and of the situation you report. And a 16.04 install overwriting a 14.04 install doesn't change anything about that.
As for a backup starting when you plug in your hard drive on your 16.04 system, that is normal: the configuration for that backup was saved in the dconf database in your $HOME when you were using 14.04, and you preserved /home.
And as for that backup resulting in a "Failed to execute child process "duplicity" (No such file or directory)" error, that again was normal: your fresh 16.06 system did not include duplicity since its version of Déjà Dup was 34.1+. As you report, opening deja-dup-preferences (the GUI) and clicking the appropriate button solved that issue.
What is not normal is Déjà Dup even trying to start a backup when duplicity is not present, instead of prompting the user to open deja-dup-preferences and request the installation of the missing software.
@Vej:
Thanks for the precisions. I still can't figure out how you ended up with duplicity installed and deja-dup- backend- gvfs not installed, this should not have happened, judging from my understanding of the code and of the situation you report. And a 16.04 install overwriting a 14.04 install doesn't change anything about that.
As for a backup starting when you plug in your hard drive on your 16.04 system, that is normal: the configuration for that backup was saved in the dconf database in your $HOME when you were using 14.04, and you preserved /home.
And as for that backup resulting in a "Failed to execute child process "duplicity" (No such file or directory)" error, that again was normal: your fresh 16.06 system did not include duplicity since its version of Déjà Dup was 34.1+. As you report, opening deja-dup- preferences (the GUI) and clicking the appropriate button solved that issue.
What is not normal is Déjà Dup even trying to start a backup when duplicity is not present, instead of prompting the user to open deja-dup- preferences and request the installation of the missing software.