Comment 5 for bug 1726873

I have the exact same problem. I keep trying and later on (without doing anything different it just mounts). I checked my .bash_history did all the same steps. No success until randomly it works. It is such an annoying bug. I had this Dir for 3 years always working, suddenly @17.10 it doesn't.
I noticed that if I use my passphrase the ID is different from what it needs, however it I add the unwrapped password the id matches.
But still I have that error