Suspicion from Crash after update to “2.0.5.1 (2.0.5.1_beta_2020-01-18)” is further confirmed.
Update from original .msi install of v2.0.2.1-2.0.2.1_beta_2017-08-01 to 2.0.5.1 does not work.
Reason is probably that the 2.0.2.1 design was replaced with a different one that is the default:
v2.0.2.11-2.0.2.11_canary_2017-10-20
Changed the way the auto-updater works. It now spawns a new version of the executable instead of attempting to run it in an AppDomain
Look in C:\Program Files\Duplicati 2\changelog.txt to see original .msi install version.
Non-Windows systems will probably reveal Duplicati’s install location in /usr/bin/duplicati script.
Web UI BaseVersionName will also show this to you, if you still have a web UI that’s working…
Among Beta releases, v2.0.3.3-2.0.3.3_beta_2018-04-02 is the first that can update to 2.0.5.1.
Old releases should be uninstalled for manual update from the .msi installer to avoid this issue.
Non-Windows systems should do the equivalent with package tools, not Duplicati autoupdater.