For what its worth this article may be of interest :-
The XML file can simply be deleted and it gets recreated from the itl file automagically.
That said the XML is effectively locked because of permissions issues so deleting ALL the .tmp files is OK and then using terminal to remove the iTunes Music Library.xml file is probably still required.
The XML is then recreated by iTunes at next launch and then hopefully keeps the permissions properly(?)
I just noticed I had this same issue minutes ago. Your suggestion, Niall Mallyon, with the Terminal commands resolved the issue. I was under a bit of distress, as I feared yet another time consuming troubleshooting issue, and didn't have much hope that something so peculiar would be resolvable through Applecare--or at least with much time wasted. So thank you so much for sharing your resolution. I truly appreciate it.
Its worth noting that I still get the issue occasionally and have yet to resolve it 100%, just work around it. I can go for days without a problem. Then it happens several times a day. I have even written an Applescript appliction to do everything to save time!
That said I am trying a different work around today that may or may not help. I discovered this elsewhere and its an interesting suggestion.
If you launch iTunes whilst holding the ALT key it will prompt you to CREATE or CHOOSE an iTunes Library. Choose CREATE and this will start a new library called iTunes 1 under the same music folder as your original iTunes library. It will be empty - don't panic. Close iTunes.
Do the same again in starting iTunes whilst holding ALT. This time select CHOOSE and then point iTunes at the original iTunes library. Everything will then return.
In my case this forced iTunes to create an iTunes Library.xml file NOT update the existing iTunes Music Library.xml file. Note the filename difference. This is interesting (But may be a red herring) because my library is very old so previous versions of iTunes used a differently named xml(?).
N.B Be sure to delete the old iTunes Music Library.xml and the newly created blank iTunes 1 library.
Now this may basically just be doing the same as removing all temp files and forcing the xml delete through terminal but it may also be that later versions of iTunes have issues with old xml file names in certain scenerios? Who knows. Time will tell but if nothing else we're trying to get around it and find a long term fix. I hope iTunes 11 is different but I doubt it. It will be all UI changes and nothing underneath I bet.
Am monitoring now to see if this helps but ML 10.8.2 and iTunes 10.7 still appear to be a problem for me.
So after couple months of trying to solve this issue, I'm still having the same problem. I tried everything. Even recreating an library folder via the XML just migrate the problem over. It's still an intermittent problem. That means for me that I able to solve the situation so a week or so and than the problem still continue.
So I contacted apple an got so good support, but the conclusion of all this with apple is that it seems that everyone that encounter this issue seem to have old if not very old iTunes library (often huge) that just kept upgrading the application over and over, years after years. If one of you it's not the case please post it.
My library is from 2007 and is 150GB of Music 500GB of Movies and much more with app and so.
So it seams in the process of updating the architecture files in the background of iTunes (in finder) are not the same. What I mean by this is that If you would start a brand new library with iTunes 10.7 the architecture of the files would be the different. That why that re creating a new library based on a old XML would migrate the problem over.
So the only way to be sure to not migrate the problem over would be to create a brand new library from scratch in parallel of the original one and import all media separately (music, movies, app, etc.). The ''new'' library would than rebuild the architecture in a modern way. It could be a very tedious job but would probably be much cleaner stronger and faster as an outcome.
For my personal conclusion, I will wait iTune 11 as Niall Mallyon suggested in October, in order to see if 11 would solve this issue. If not I will this huge task of re importing all my media in a new library and should be expected to be done by 2019…
Joke a side I will wait iTunes 11 and then decide. Mine while I tolerate and monitor this problem in the finder.
Please I would like to know your perspective on this point gentlemen.
Keeping you posted with the update.
Have you tried the CREATE/CHOOSE option I described above ??
This seems to have stabilised the issue for me at least over the last 48 hours or so.
I'm convinced you are correct in that old libraries are an issue but as to the architecture differences the main files are still held in the iTunes folder but their names appear to have changed, for the XML at least.
I cant see how importing afresh will solve things. Its not the ITL file thats at fault only the XML.
Try the CREATE/CHOOSE option and see if this helps.
Problem has reappeared again - ahhhh!!!
I do however know reason it happened in this instance but I have no idea how to resolve it.
The problem occurred when I downloaded an updated app via the iTunes store. The final step in the update is to 'process' the download. This stalled for quite some time during which the iTunes Library.xml file permissions became correct and a temp xml was thus left behind.
I can't understand why after what is nearly a month this rears its head again. Its by far the most annoying problem I have ever had with my Mac.
I'm convinced iTunes 11, which I'm guessing will be out really soon (if not today as its the 23rd 'mini iPad' day) will NOT fix the issue. Its clearly a bug in the iTunes process and app as a whole as this has occurred in previous releases.
Ah no! Are you serious?!
I did the update yesterday. So far I'm ok. But I will keep you posted about this.
I must say I'm not that pleased with itune 11 it self. And if on top of this it does not solve our problem.
They took out itune DJ which I just don't understand why.
Any ways if the problem aprear again I will re create a librairy and re import all the media again. Not happy about this at all....
Why apple have to screw things up latetly.
Hard to not blame it on the absence of Mr. Jobs.
It definately only happens when iOS apps are being updated. I have had no issues with adding CDs but then again I upgrade apps far more than adding music.
Beats me why, when the XML is ONLY used by iTunes for sharing info with other applictions, that theres an issue. I don't share my library OR have home sharing turned on.
I just want it gone. I may have to export all my play lists, scrap the library and recreate it. Maybe that will help but it doesn't see well documented and is not for the faint hearted.
For the record: one more here with exact the same issue. One more in a list of many. In my opinion iTunes 11 is one of the worst releases of Apple software in a long, long time. Specially if you realize that iTunes is strategically one of Apples most important pieces of software. I love Apple but I have to say the screwed up this one big time.