Moved my music - playlists now not working

Question

Dear All,
I've just gone through a fraught time during which I've cloned my system, got rid of HD partitions, and restored my cloned OS. One reason for doing this was to shift all my music from an external HD to my Mini.
However, being an inconsistent (and in hindsight, rather stupid) human, I think I buggered around with the iTunes library files (ie Trashed them) before copying the music over.
In a second attempt, though, I think I must have put some of them back in place, because iTunes has now remembered my playlists, of which I have quite a few.
The music in my library is fine: everything seems to be in place, referenced correctly, and plays.
Unfortunately, the same can't be said for my playlists, every track in which is not located, showing an exclamation mark, offering the option to locate each track manually.
Is there a way to 'bless' the music in my playlists automatically, or am I now in the position of making them all again by hand?
Thanks,
Matt

Answer 1

Hi,
Thanks for the response, and for what seems to be a good workflow, which I'd love to have tried.
I wish I still had the clone to work from, but because the whole clone/restore fiasco cost me five or six days of brain-fry, I think I was just glad to see the end of it! A classic case for some Schadenfreude...
So, I fell at the first hurdle in your advice, and being as I couldn't be sure which copy of the .xml file I had, I didn't continue with the rebuild.
So I used two methods together:
I had managed to save most of my playlists as .xml files within my personal data folder (missing a couple, and a few out of date compared with changes I'd made to the original files - genre changes, for instance), but I wasn't sure the new location of the files would affect the import, or not, and not all playlists had been saved.
Hence the need for the second approach: print playlists, sorted by album for shuffled playlists, or in order, where appropriate.
This helped maintain the order of the tracks in ordered playlists, so that when adding the missing tracks back, they could be placed in the right order. The paper version was compared against the re-imported version, and missing tracks were then added back in. Of course, saving and overwriting the exported playlists was the final step.
Some artwork has gone missing along the way, but all in all, it's going to be about four hours work - not too bad, considering how bad it might have been.
As a final rub of salt in the wound, and confirming the fact that these things come in threes, I've also got a 42404 error in iTunes, which stops me playing my iTunes Store purchases. I'm now backing up my whole library to disc (all fourteen DVDs of it!), before uninstalling and reinstalling iTunes, and checking QuickTime version...
Wish me luck & thanks again - glad somebody got some good help from it - good links to Doug's scripts.
Matt