Troubleshooting

Add Pre-existing Series to Sonarr

Existing files should be in a folder for each movie.
Movie › Bulk Import Movies › /data/tv
Be sure to set appropriate import behavior.
Be sure to search for correct match for episode if needed.
Add all existing shows (even no longer aired), these are all scanned when adding shows and will be crufty if not set.

Changing Media Location in Series

If series were imported under a different directory initially, these can be updated.

Series › Series Editor
Select all series that had location changes.
Root Folder (lower right) and enter new folder location.
Save

Ensure no Duplicate Plex Updates

Plex will trigger updates on inotify events if configured to do so. If that is the case: Connect › Plex › Update Library › Disable.

Otherwise duplicate items will appear on single files.