The “Test connection” step is more of a “can we actually log in” test then a full “can we do sustained reads / writes” test - so it’s possible the destination or network connection involved my be able to handle short connections but have an issue with longer data transfers under one or the other protocol.
Since the missing files include dblock files that means some of your backed up data is now gone. Because Duplicati only backups up changes to files it relies on the existing backups to be valid - since they’re not, by default it won’t let you add more backups on top of a possibly incomplete “base”.
At this point your options are to:
-
run the database “Recreate (delete and repair)” step (easy to start but potentially VERY long running)
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use the
list-broken-filesandpurge-broken-filescommands to see what files are affected and remove them from your backups (see below - this is likely the fastest way to get things going, plus you’ll know what backup files / versions were affected) -
add a parameter that lets you ignore the error (definitely NOT recommended as restores may not be viable)
Here’s a guide on how to list and purge broken files: