Do you experience problems during downloading?
Check your connection in Status and Interface settings window.
Use Test Server in Config > Servers.
We will probably ask you to do a test using only basic settings.
Do you experience problems during repair or unpacking?
Enable +Debug logging in the Status and Interface settings window and share the relevant parts of the log here using [ code ] sections.
Going from 2.1.0 on ubuntu 17.04 to 2.3.1, I now get this error when browsing to config page (cannot post stracktrace because "New users are not allowed to post links")
It seems some Config template files were not updated correctly.
I think the safest is to remove sabnzbd completely (your settings file is stored seperate so should be preserved, but doesn't hurt to make a quick copy of it, location is shown on first page of Config) and then double check that the installation folder (also shown on first page of Config) is completely gone.
Then reinstall sabnzbd.
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