I just finished moving my library from one NAS to another. I too had difficulty getting MediaMonkey to find/locate missing tracks when performing the operation on the entire library at once. Spent a lot of time trying to make it work. Performing find/locate on individual collections of my library at a time did the trick.

I am guessing that it is not so much a large library issue, but a file structure/collections issue. I have 36,631 files in my library.
I have Music, Podcasts, Import Quarantine, Videos, etc. as different collections stored in different folders.

Windows 7 Home Premium
MM version 4.1.10.1778

That may be quicker, but unfortunately it's not the way all the regular documentation says to do it! And it really *should* work regardless - it's not an extra feature request, it's a shortcoming of a current one.

I would send a debug log, but unfortunately all is good now and I don't have the time to re-do the whole thing, it took me quite a while.

Quicker: http://www.mediamonkey.com/wiki/index.php/Moving_MM_to_a_new_computer

Sending a debug log (step 4b) for this to support would be good: http://www.mediamonkey.com/forum/viewtopic.php?f=7&t=69

I recently formatted my computer, and have not been able to get my MM library back to it's usual state. Here's what I did, with the problem at the end:
1. Using MM 4.0.2, moved the database to Dropbox, and pointed MediaMonkey.ini to it (it has been there for months with no problem - quite handy for continuous backup)
2. Copied all my music (C:\Music) to an external hard drive
3. Formatted my laptop & reinstalled Windows
4. Installed MM 4.0.1 (as using ninite - seriously handy site, check it out), ran once and upgraded to 4.0.2.
5. Edited MediaMonkey.ini to look to Dropbox for the database (exact same path as before, but that shouldn't matter)
6. Ran MM, expecting all the music to be there as before; it wasn't. Everything was there, but greyed out. I noticed that the paths for everything had changed from 'C:\Music\' to '[]\Music'. So, I clicked on Entire Library and selected everything, then used Locate Moved/Missing files to find everything. I think it's quite important to point out that the directory structure had not changed at all, it was all still in C:\Music, and I defined this in the Locate Moved files dialogue box. However, MM will only find certain tracks. There seems to be no rhyme or reason to it - certain folders/albums have tracks missing.

I really don't want to completely remove and then re-add everything, as I have lots of playlists that would take an age to rebuild.

Screenshot for clarity...

http://i.imgur.com/ZnsnY.jpg

EDIT:

I managed to resolve this by doing each subfolder of C:\Music individually. A pain, but not the end of the world. There are just over 11,700 tracks in my collection, and first time round it found about 3-4,000 (I didn't check :roll:). I think implies that there is something wrong with MediaMonkey rather than the way in which I was doing it. It is probably also worth pointing out that even though the tracks were unplayable, greyed out and had the path starting []\Music, they didn't appear in Files To Edit\Dead Links.

So yeah, more of a bug than need for help, I think :wink: