Hi *, I suspect it’s not the precise issue the OP encountered, but since search led me here, I’m bumping/necro’ing this one.
I got this error (“The socket has been shut down”), when setting up duplicati with AWS S3.
After some trial and error I think the problem was the specification of the “subfolder” in the S3 bucket that the backup was directed to.
My configuration was like this (I took over the default here):
[Page 2 “Destination” → Backup Destination → FolderPath]: “/home/alex”
Whereas a copy of the configuration with the empty string instead worked.
(I had to repair database in between, since changing this entry seems to confuse duplicati)
I suspect that object key names in s3 cannot start with a /, but did not find hard evidence so far.