Please don't make such assumptions. Strange problems are often caused by antivirus software, and you've got some strange problems. The only way to prove that eset is not at fault is to uninstall it.
I would be happy to try that if there was a test (or method) to determine why a library that was showing 100% thumbnails yesterday is showing 54% now AND that ESET is somehow involved but since my only choice now is to sit here for several days and rebuild them again - I can't seriously consider removing it.
Process Monitor (SysInternals) shows no activity of any kind from ESET when MC is running, building thumbs or doing anything else.
I am shifting my focus to the library itself. The possibility of this thing being corrupted is much more likely than ESET trying to jump in the game.
Do I recall correctly that you have MC accessing the same data directly from multiple machines, and you're not using MC's Library Server? Maybe you've said above.
Yes. This install with the issue is my standard local install. The music locations in the library (all FLAC) do come from our music share. We do have a library server on a dedicated HTPC but this problem is not about connecting to that as a client.
And lookee here - just for kicks - I popped out the server. Check out what is happening with it's thumbnails (See attachment)
Just 5 days ago - I confirmed the server was at 100% thumbnails on 9/2/2018. (See additional attachment showing thumbs directory after 100% update a few days ago)
Seems the new thumbs folders were created at 9:55am this morning - and the files are much smaller than the 9/2/2018 fileset....this is bizarre
The only thing I did this morning was launch a "client" machine that connected to the server. Could this simple connection start the thumb-nailing all over again?
VP