Rename, Move & Copy would not be very suited, since this was about 100Gb of files on a NAS. I did not have the opportunity to keep my computer on for the whole job, so i made a backup job that could resume whenever my computer was online.
That's fine. I also prefer to move big chunks of network files outside MC. There is no reason to move the files over the network if they can be moved faster and safer on the server PC.
I guessed this would happen, but hoped that I could delete the new imports, and do a "find & replace" on filename on the old instances. But I seems to still import the new ones, so that I get duplicates. Should not filename be unique constrained?
As I said, Auto-Importer is not the correct tool for this.
The filenames are indeed unique (including the paths) and MC cannot just automatically detect if different files happen to be identical. It would need to make a bit-to-bit comparison against each file. For instance, if you have 100 old and 100 new files this would mean 10000 full file comparison tasks EDIT: actually, if the files are already moved there are no old files so it would be impossible to compare them. It could work only if the files are in the both locations, but then the library links would be fine.A few months ago JRiver introduced the redesigned Rename, Move, & Copy Files tool. It can now apply changes only to the database if preferred.
It can easily change "X:\movies\" to "Y:\1 - Movies\" in a few seconds in case the files are already moved outside MC.
Maybe you could restore your latest library backup, switch Auto-Import off and fix the paths with the RM&CF tool as I and darichman suggested. Alternatively you can still use the old method, which is to use the Find & Replace tool for fixing the Filename(path) or Filename field.
Also, the MPL system should work:
1. Disable Auto-Importer
2. Select the video files (restore a library backup file if the library doesn't contain the old file locations anymore)
3. Export the playlist to X:\Movies\ (enable the relative paths option)
4. Remove the video files from the database
5. Move the MPL playlist file to Y:\1 - Movies\
6. Import the MPL playlist by using the File > Import Playlist tool. (You need to select the "Common playlist types..." option in the "Files of type" drop-down menu.)
-- If you have static playlists of these video files you will need to export/import them separately because the old static playlists will be emptied when you remove the old files from the library. The "relative paths" option will work also with them.