After working OK for a few weeks, Deja Dup backup failed with the following message:

"Error calling StartServiceByName for com.ubuntuone.Credentials: GDBus.Errorrg.freedesktop.DBus.Error.Spawn.ChildExited: Process /usr/lib/ubuntuone-client/ubuntuone-login exited with status 1".

I tried reloading the software without success.

I'm assuming a recent update may have scrambled it. I'm wondering whether it has something to do with my recent decision to revert from Unity 2D to Gnome Classic.

Any suggestions?