Want to sync your iPhone across multiple computers? It’s a bit of a hassle, but here’s how to do it in iTunes 10. You may remember a while back we explained how to do it with older versions of iTunes.
This fix comes from MacRumors forums user fasttimes. According to the post it works on both Mac and PC. Here it is. (Note: We have not tried this one yet, so use at your own risk).
Please hit the jump to read the full tutorial.
1) Uninstall iTunes on all your extra machines, and delete everything in the directory that has the iTunes Music Library.XML and iTunes Library.itl files.
2) Install iTunes 9.2 (you can find it here)
3) Follow these steps:
Apple only allows you to sync your iPhone with one iTunes library at a time. When you attempt to sync your iPhone to another computer, you get the following message.
Note: “Computer 1″ represents your usual computer, “Computer 2″ represents the new computer you would like to sync your iPhone to.
On “Computer 2″, backup “iTunes Music Library.xml” and “iTunes Music Library” (Tunes Music Library on Windows) safely.
Download a Hex editor.
1. On Computer 1, open “iTunes Music Library.xml” with Notepad and search (Ctrl+F) for ”<key>Library Persistent ID</key>”
2. Following ”<key>Library Persistent ID</key>”, copy the code between <string> and </string>
In this example it is “8B6C633F7DACB74B”.
3. On computer 2, find that same code, and replace it with the code from computer 1.
4. Open “iTunes Music Library” (iTunes Library.itl on Windows) using your Hex Editor on computer 2.
5. In the Hex Editor, go to Edit > Replace.
6. In “Find”, insert code from computer 2. In “Replace With”, insert code from computer 1. There should be one match.
7. Save this file. Close it.
4) Unplug your iPhone.
5) Launch iTunes with auto-sync turned OFF
6) Plug in your iPhone again. Check your iPhone’s App page in iTunes. Check the “sync” checkbox and you should not see the message about removing your old apps.
7) Right click on the iPhone and transfer purchases.
Now you should be able to install iTunes 10 and sync both machines.
[Credit to fasttimes - Link]
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Doesn’t seem to work with OS X Lion / iPhone 4 – when plugging in the device with iTunes 9.2 I get an alert:
Ignore that. Despite that message, after installing 10.4 it works. Thanks!
OS X Lion won’t allow you to delete iTunes. If you try, you are met with, ‘“iTunes” can’t be modified or deleted because it’s required by Mac OS X.’
Thanks, we gonna take a look and see if steps have to change because of that
I just got it working on Lion. You don’t need itunes 9.2. Close itunes and itunes helper. Then edit the two files as described. After that is done, clear the itunes cache folder and preferences. Then launch itunes again and voila!
Brilliant, so simple.
Sorry if this a dumb question, I’m new to macs but I’m a quick learner. How do you clear the cache and preferences?
I tried the method above, but it didn’t work.
OS X 10.6.8.
iTunes 10.4.1.
iOS 4.3.1.
Just an update:
I was able to get iTunes to generate a new iTunes Library.itl by opening up the iTunes Library.itl in TextEdit and completely clearing it and saving it. The new file has the Library Persistent Id that I had transfered from my other computer already. So now it works.
Thanks JF, it worked for me!
Same here! Great solution! Thanks!
(OS X 10.6.8, iTunes 10.5, iPhone 4)
Worked here as well!
Thanks all!
you my friend are a legend! been trying everything else under the sun and hasn’t worked, champ.
You are a genius! It is such an easy fix!!!
worked like a charm, thanks
I’ve updated to iOS5 on my iPhone and it needs the latest iTunes to work, does anyone know a fix for this?
that is the only way, update to the latest itunes
Well that did not work at all. The warning message is gone, so it seemed like it was going to work. Now I have a phone with nothing on it but the default apps.
It did make a backup before syncing, but even after restoring from backup, nothing is there. Looks like I will have to restore from main computer at home.
Previous post said I lost everything when trying this trick, but after downloading all purchased apps and tunes into the new installation of iTunes, I was able to restore iPhone back to the backup it made when first syncing. So this works, just be aware that nothing is copied from phone into iTunes, you have to first populate iTunes with stuff before it will be synced to the phone.
Just wondering… If I change the library persistent ID key from the computer 2, replacing it by the one I have in computer 1, and I already had an iphone sync with itunes from computer 2, will there be any problems when trying to sync again that iphone with itunes from computer 2?
Can anybody help me, i already try the suggestion from Tomas, but still not working..
Everytime I start the Itunes after all the steps suggested, it still give me a warning message that my current app in my iphone will be erased, if syncd with my new computer.
and if i check the “itunes music library file” the code were changed back to it’s original..
please help..
as i need to get rid of my old computer asap.
too old, thus too slow…
thanks before..
I’m having this same problem. Doesn’t seem to save the replaced ID key.
Any thoughts?
What if I can’t I can’t access my old computer (1). How can I sync with a new computer (2) and keep all my data on iPhone?
Hi Everyone!
This method work without downgrading or downloading anything! Right off the bat with iTunes 10. Already mentioned kind of, but it doesn’t hurt to re-iterate.
You can skip the Hexeditor part if you are starting your new iTunes from scratch. After you change your “iTunes Music Library.xml” file, open iTunes Music Library with TextEdit application delete a bunch of characters (go crazy!) and save. Open iTunes and it generates a brand new library with the correct persistent ID. It will give you a message that a new library file has been created and that the old one has been renamed “iTunes Music Library (Damaged)” Your phone now syncs! If you want to get your music off simply download iRip!
i followed this advice and it deleted most of my iphones memory taking me from 1060 songs to 186 without my knowledge. Thanks for that you have riuned my iphone
The above did not work for me. However, it did set me on the right path. I first followed all steps (latest itunes version) and then (without reinstalling or restarting) copied my backed up ‘iTunes Libary.itl’ to my new OS. Note that it was just and only the itl file, not the XML file. Copying both caused itunes to freeze.
i just copied and pasted both files on new computer. it seems to work
Guys. Why all the hassle?
1. In the new computer, delete the “iTunes Music Library.xml” file.
2. Replace the new “iTunes Library.itl” with the old one from the old computer.
3. Sync.
*YOU MUST BRING OVER WHATEVER MEDIA FROM THE OLD TO THE NEW,
E.G.; PODCASTS/MUSIC/MOBILE APPLICATIONS/BOOKS.
JUST DRAG IT OVER IN iTUNES!
This sounds easy enough, but how are you supposed to replace the old from the new??
It works!!!!!!
Is this really nescesary? Why can’t the pinheads at iTunes make it possible to load music or movies into the iPhone by dragging from windows explorer? I can do that with my windows phone.
No wonder my last apple was a Macintosh. Apple software sucks.
will this also backup the mobile sync? sms messages on the new computer?
OK, I must be having a blonde moment!! When I open up the Itunes music library to change the code, it doesn’t allow me to delete the code that is already there and replace it with the new code?? Can someone “dumb” down these steps for me.. PLEASE!!