Something that came out from discussion in Some feedback and experience with a restore was that there may be some backup files that are corrupted.
How do I check the entire backup (or backup files corresponding to specific source files) ? I used verify option in web interface but from logs it seems to test only a small random sample of backup files…
The TEST command and Using the Command line tools from within the Graphical User Interface can verify “all” remote files are downloadable and decryptable. They can optionally be verified even more.
This can be a big download (an issue of time and maybe cost). Possibly it would be less downloading performing an actual Restore of something like the most recent backup, specifying –no-local-blocks to ensure that all of the restored file data comes from the backup rather than from original source files…
Somewhat longer, but an even better test, is to Direct restore from backup files onto a different system which gives you confidence that Duplicati can do a restore if your drive dies and its database gets lost. Direct restore builds a partial temporary database. If you try this, use 2.0.5.1. Earlier versions are slow.