Usually I'll recommend unchecking and rechecking the read itunes library option.
Sounds like you covered that. have you since played the music in itunes to make sure it is there and will play?
Here is an article we made on how to move your itunes playlists into Scratch Live crates -->serato.com
As we have seen over the many years, having Scratch Live read the itunes library is not a rock solid solution. None of us in Rane tech support would recommend it and we all try to steer people from it. This is one of many reasons. Mainly the problems have been the two libraries not matching up and also the library not showing up at all. That can be a nightmare for dj's. This usually occurs each time itunes updates its software.
What we recommend is that you manually import the music into Scratch Live using the 'Files' tab on the main page. It is still o.k. and common for people to use itunes to rip cds and create the needed song files that will wind up going into the Scratch Live library. Ideally you would organize you music files in your own folders. I have a hip hop folder, a rock folder, a reggae folder ect. Once the music is organized on my HD it is very easy for me to open Scratch Live, make a new crate called hip hop, rock, reggae and drag those songs from the folders into it.
This way the music is already organized. You can do all of your tagging changes directly in Scratch Live. We recommend using the crates and smart crates in the software in the same fashion you have been using your playlists and smart playlists inside of itunes. Also in the case of you get to a gig and open the program, but you don't see any crates (currently you have no playlists) its not a show stopper. Simply make a new crate, open the Files tab, drag the folder back into the program and you are ready to gig again in only a few minutes. It's in instances like these that the itunes library stops showing that can take hours to repair.
Here is an easy way to keep everything up to date in your library. If you have a hip hop folder with 1,000 songs make a new crate and call it hip hop. Drag the hip hop folder into the new hip hop crate, simple. Now if you add 100 new songs to the hip hop folder, open the files tab and drag that hip hop folder back onto the original hip hop crate. By dragging the same folder to the same crate, it will only update the crate with the new additions instead of doubling the music. If you dragged that hip hop folder onto your rock crate though, it would add all 1,100 files
In the past we have had people try rebuilding the itunes library but lately we have seen odd characters in the itunes id3 tags causing problems reading that library. There was a tag checker we found on the apple website. Give this a look over and hopefully this can help remedy the issue. Ultimately though, I would start to consider not using Scratch Live to read the itunes library.
Link to apple discussion - discussions.apple.com
Link to suggested solution - mac.softpedia.com
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This person was using Idjay software and had a similar issue, here is how he solved it - forum.algoriddim.com
1. Open itunes, sort the library by Date added
2. In the library go to the song(s) added on the day and time your itunes music library.xml was last modified (stopped working)
3. Opened up the file info for the particular song that was added the day the .xml was last updated
4. Look for non-english characters inside the song's info like title, artist, album, comments, etc.
5. Delete the foreign characters, check for the next couple of songs, especially those added after the date of .xml was last modified.
Checking your XML modification date and comparing it against the Date Added field of your library is another method of checking for bad files / foreign characters.
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XML creation crashes on some of the characters that it's unable to convert to XML-entities correctly. - discussions.apple.com
1. Create new smart playlist with a rule 'Playlist is Music'
2. Set limit to approx half your library size, ordered by Artist
3. Try to export the playlist in XML via File -> Library -> Export playlist
4. If the file has been created, delete it, increase the amount of songs in your smartplaylist; if the export has failed, decrease limit by a certain amount of songs.
5. After several tries you will find a limit number after which the creation fails. Go down to the end of this playlist and check the info of the file.
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Here is a combo of those two methods that a Traktor user found successful. -
1. Open itunes library and sort by date added
2. In the library go to the song(s) added on the day and time your itunes music library.xml was last modified (stopped working)
3. Find the songs right around that date and make a smart playlists for those albums
4. Try exporting an .xml file for that playlist.
5. If it fails narrow the search, if it exports, expand the search with songs after the last time the .xml updated
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Links to different xml validator tools ----
A traktor user was having a similar issue and the Native instruments team suggested - www.native-instruments.com
Make sure to take out any non-music files i.e. movie files, video m4a files, etc.. Files containing illegal characters in the name may also cause problems, i.e. ' '{' etc..
The following tools can also assist in tracking down corrupt files in your
collection and in some cases even repair them:
PC - mp3val.sourceforge.net
MAC - triq.net
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forums.macrumors.com
Opened up my itunes library.xml with textmate and ran the XML syntax validation. It found that there were two songs which contained invalid characters in their metadata. I removed those characters and voila the import playlist completed
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discussions.apple.com
For anyone in a windows environment - there is a free tool downloadable called cooktop that is a simple to install xml validator and found the offending song in my library in seconds.
www.perfectxml.com
xmlCooktop program
**Interesting note : This led me to find that a 'dropbox' type application called Zumodrive that allows you to share your music from iTunes library so you can play from your iPhone at any time was holding the iTunes Music Library.xml file open and not allowing iTunes to update it so Serato was opening a stale copy all the time.
Hopefully this will be helpful.