Hello All, So, I figured I'd ask and see if anybody else has stumbled on this weird issue, and perhaps has a solution. I have been using my Mac Pro with El Capitan 10.11.6 to host my iTunes library for my Apple TV's in the house. Recently, it seemed like it would be a good idea to move that task to a machine which consumes less electricity. So, to keep things simple, I set up another computer with El Capitan 10.11.6. I also installed the latest version of iTunes 18.104.22.168 on it (the same version that has been running on my Mac Pro). I felt that by keeping everything essentially identical, that the move would be simple and smooth. My iTunes library has always been hosted on an external drive (6 Terabytes), and I have always had it set to keep the library organized, and consolidated. That way everything that I import gets brought into the library. Just to be sure, I manually ran through the consolidation and organization routines before beginning the move. My Library is located at: /Volumes/iTunes/iTunes Archive/iTunes Library I shut down iTunes on the Mac Pro, ejected the iTunes drive, and then plugged the drive into the replacement Mac, opened iTunes while holding down the "Option" key so that iTunes would ask me where to find the library. I pointed the machine to the same location stated above, and iTunes launched and appeared to be fine. The immediately noticeable problem, is that it doesn't see all of the titles I have. On the Mac Pro, my library has 13,540 songs, 1,281 movies, and 1,996 TV Shows. On the new Mac, it is 11,200 songs, 541 movies, and 800 TV Shows. I've looked through every option I can find to make sure that both iTunes installations have the exact same settings. Both are definitely pointed at the same location (I've double checked that in the Advanced preferences tab). Worried that I had damaged my library, I moved the hard drive back to the Mac Pro, and launched iTunes. My numbers are exactly as they should be. Unplug the drive, take it back to the new Mac, and my numbers are lower again. I've verified that the music is in-tact and playable (likewise with the movies and TV Shows) when brought back to their original Mac Pro. But, every time I take it back over to the new Mac, it goes back down to only seeing a portion of my collection (consistent numbers with the above stated). I've done this before without any trouble in older installations of iTunes. I've never had this weird glitch. I've rerun the consolidation routines on both machines, and the results stay the same. I haven't made a recent backup of the hard drive, so I might do that before any more tinkering. But, I thought I'd go ahead and ask if anyone else has seen this before, and how they fixed it. I have numerous playlists that I'd prefer to keep fully intact, they're quite a pain to rebuild (large complicated rules and such). So, ideally I'd be able to just take the drive over to the new machine, like I have before. The new machine is a fresh install of OS X 10.11.6 El Capitan and iTunes 22.214.171.124 (exactly matching what I have on the old Mac Pro). I have already signed into my Apple Account, and authorized the new machine to play content. So, that's not the problem. But, even so, most of my collection is CD and DVD rips, so the authorization would be a much smaller number if that were the problem. So.... any ideas about this strange iTunes glitch???? Perhaps somebody has dealt with this one before.