Ok, after an hour on the phone with a nice Apple guy wh told me there is no way possible to go back if you have a library.itl error I decided to just hack the program.
Here was my issue:
i have a 3TB iTunes library which is comprised of my own Cd collection (about 4000 discs) and HD downloads. The total library is about 4400 albums.
I use a core 2 duo Mac Mini as a home server, as it is powerful enough to serve the house with my entire media content (music from iTunes and movies populated on external discs connected to my Mac Mini).
A friend gifted me a new Mac Pro (black garbage can style) which is running Yosemite and the latest (red) iTunes. When I opened my iTunes library with the newest version of iTunes, it would no longer open on my Mac Mini which can only run Lion and iTunes 10.7. I got the dreaded library.itl error and a rediculious insult from Apple suggesting I search for a newer version of iTunes, fully aware that mine is the latest and I am FUBARed relative to using my library again on my Mac mini.
Thanks Apple...... (I miss Scott Forsill and his software ideology BTW)
The Solution:
1. With the external 3TB drive connected to my Mini, I opend the ITunes library and dragged the library.itl out of the folder. (Thus preserving it for future use on the Mac Pro).
2. Option-clicking the ITunes app I launched it and made a NEW iTunes library on my desktop (thus the internal drive).
3. I dragged an album onto the iTunes icon to import it and thus make a library.
4. Closed the app and then copied the library.itl file into the iTunes folder on the 3TB drive.
5. Option-click again and select the iTunes folder on the external drive
6. Take a deep breath as it will launch and show only one album (which ironically is not actually there)...... but relax.
7. From the file menu I chose Add to Library and navigate to your media folder where all my music is and went to bed.
The Result?
I ended up with a 94% fix. Almost all of the albums are there, with proper meta data, covers and order of release (dates and such are fine).
However, I have about 300 discs which need covers (which the iTunes Store cannot find for some reason - probably HD tracks albums which I have labelled with the sample rate ie: Dark Side Of The Moon 24/192.
I also have an issue with some albums which ripped as a single file, because of issues with the original disc..... and I need to fix those.
so there you go.
A Solution, ....... and I remain open to any suggestions as to how to repair my database without having to manually access each file.
NOW,... Have any of you code-heads ever looked at the library.itl file to see if it can just be modified????