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jclardy

macrumors 601
Original poster
Oct 6, 2008
4,282
4,733
Has anyone synced to multiple computers, getting music and photos off of each? I am hoping you can but from my experience it doesn't seem like you can...here is what happened to me:

I synced the first time with my macbook, disconnected and starting downloading apps. Downloaded OmniGraffle and created a diagram for a class I am taking. I bought a movie and downloaded it so I wanted to transfer it to my parent's iMac (Which is linked to my iTunes account) So I plug it in and try to put some photos on my iPad. I click sync and it starts copying my downloaded apps to the iMac. Then it deletes all my apps, including OmniGraffle and my diagram. The thing is, it never popped up asking me to Erase and Sync like with iPhone/iPod Touch...so i'm wondering if you can sync to multiple computers? (I would try but I want to sync to my home Mac Mini and I don't have access to it until Monday)
 
I would *assume* it's like an iPhone, it wants one home machine, and that's it. Else, it assumes you got a new Mac/PC and are starting over. But if it didn't ask, that's extremely weird.

Remember that it's a modified iPhone OS (whatever you want to call it), so most things operate the same way. I would be shocked if syncing was different. So this is strange.

Anyone else want to try this? On a new one before it's full? I'm getting one today and could give this a shot, if I can remember to.. :)
 
I got warning messages

That the apps would be erased - didn't try to sync it after I got the warning message. Its distressing to hear it wiped out the app and the associated data. I have synced an iphone with pictures from one computer and apps from another but the iPad won't work in that configuration. When I disable app syncing it gets turned on again when I enable the photo sync. I am going to try it the other way around - sync the photos and apps from computer 1 then try syncing just the apps and mail from computer 2 - anybody try this yet?
 
I have found this tip and thought that is worth sharing

http://www.theipadguru.com/2010/05/18/guru-guide-sync-your-ipad-with-multiple-computers/

there you can see how they manage to hook the ipad to more than 1 computer. Tried that one on mine and it work as well.

From the dawn of the iPod, it seems that it has been Apples mission to ensure that your device is tied to one computer and one computer only. To say that this is annoying and impractical is making a huge understatement. If you own a device, the machine that it’s being hooked up to and the content that you’re transferring, why are you limited to just linking that device and computer once? Well the point comes down to money. The record labels providing the music would love to see users confined to using and sharing music according to their rules, usually rules that involve them making the most money.

Too bad it’s so easy to just ignore all of that and do it anyway…….

This guide is set up to allow you to do two simple things, one, get the iTunes ID of your computer, something that iTunes and your device use to verify that they are “mated” so that they can communicate properly. Then, we take that ID and apply it to the other computer that you want to use your device with. This is most ideal for situations where you want to sync your iPad with say a laptop and desktop that have different music on them. For instance, if I wanted to listen to some Sugarland or Rascal Flats (not likely), I would need to mosey on over to my wife’s library and get them out of there. Can’t do this if the other computer’s iTunes wants to wipe my device and overwrite it with neuvo-country (shudder). So, here’s how we go about this….

Start here if you have a PCiPad, move on to the Mac Method section if you have a Mac

Windows Vista Method

First download HexEdit, you’re going to need it.

Navigate to your Music folder, then the iTunes folder….

Right click the file named iTunes Music Library.xml, choose open with and Notepad.
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Copy the Library Persistent ID key and paste it into a text file or write it down. It should look something like 456e20293961CBA4. Do not save your changes!

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OK, time to move on to your second computer, the one you want to sync to in addition to your primary.

Lets back up iTunes Music Library.xml and iTunes Library.itl before we go mucking about with them. Go to Music>iTunes, select the two files and press ctrl+c and ctrl+v to create copies of the files.
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Right click on your iTunes Music Library.xml and select open with, Notepad to open it.

Find the same Library Persistent ID key, write this one down just in case, and replace it with the one you copied from your primary computer. Make sure you type it exactly right.
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Now open up the HexEdit program you downloaded at the beginning, you did download it right? Now open iTunes Library.itl in HexEdit.
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Hit Find in HexEdit and select Hex as the Find type. Then type in the original Library Persistent ID and hit OK.

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Once you find it, replace it with the new Persistent ID from your main computer, type it exactly in pairs of numbers to replace the original. Do it exactly or you will screw up your iTunes library file…but this is why we made backups! You didn’t skip that step did you? Of course not.
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Now open iTunes, plug in your iPad and click Manually Manage music and videos. Notice no annoying “erase your iPad” message? Proceed to manage music to your hearts content from either machine!
Picture 19

Mac Method

We’re going to need HexEdit, make sure you get it from here.

Press Command Spacebar and type in “iTunes”. Scroll down to the folder that says “iTunes – Music”, not “iTunes Music” and hit enter.
Picture 20

Double click the file named iTunes Music Library.xml to open it in TextEdit.

Picture 23

Write down the value of the Library Persistent ID key. Take care not to modify the file before closing. It should look something like A4E3DEFD1E51FF94.
Picture 24

Now go to your second machine and repeat the above steps, once you have your iTunes folder open however, make sure to select both iTunes Library and iTunes Music Libraby.xml and press Command+c then Command+v to make copies for backup first.

Now double click to open iTunes Music Library.xml.

Change the Library Persistent ID key to the one from your main computer and save the file.

Picture 24

Now, use HexEdit, you got that above right? Open the iTunes Library file in HexEdit. Once you have opened iTunes Library use HexEdit to search for the old Library Persistent ID we replaced in Step Five. Do this by clicking Find from the Menubar. Make sure to select Hex as your search type.

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Once found replace the old Library Persistent ID with the one from your main machine and save the file.
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You can now launch iTunes and connect your iPadiPad to the new computer for syncing, feel free to select Manually manage music and videos and manage away on either machine!

Picture 19
 
is this method now broken?

i copied the persistent id from my mac that contains all the media which my iphone was originally synced to.

opened itunes music library xml and changed the id on the new machine with the one from the old one using textedit.

opened the itunes library on the new machine using hexedit, and changed the old persistent id to the new one as above.

save both. still when i hit "manually manage music" i get the annoying "synced to another library".

what is going on? am i missing something?

p.s. after i reboot, the values go back to the old one...
 
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You have to authorize more than one computer for the same iTunes account to do this but it's pretty easy.

For example, if Movie 1 is on your parents' iMac and Movie 2, Apps 1-90, and Music are on your mbp and you want to put Movie 1 on your iPad in addition to the content on your mbp, authorize your parents' iTunes account onto your computer. Each iTunes account can have up to 5 active computers at any one time.

From there, transfer your content via USB or FireWire to your usual syncing computer and iTunes will allow you to put content from your parents' iMac onto your iPad (or vice versa of course).
 
thanks for getting back to me.

so my itunes is authorized to the same itunes account, even before i started attempting to do all this. one thing i did do, was to authorize, uncheck manually manage music, and also keopt unchecked music sync, and sync'ed over my contacts and apps.

do you think that might have something to do with it?

i see that i'm not able to download updates to the apps in the secondary computer... it tells me that i have to have one central computer in which to purchase, update, etc. and then those will be automatically updated to other authorized machines.

maybe in lieu of this icloud autoupdating authorized computers has broken this trick somehow?
 
thanks for getting back to me.

so my itunes is authorized to the same itunes account, even before i started attempting to do all this. one thing i did do, was to authorize, uncheck manually manage music, and also keopt unchecked music sync, and sync'ed over my contacts and apps.

do you think that might have something to do with it?

i see that i'm not able to download updates to the apps in the secondary computer... it tells me that i have to have one central computer in which to purchase, update, etc. and then those will be automatically updated to other authorized machines.

maybe in lieu of this icloud autoupdating authorized computers has broken this trick somehow?

Oh, ok I see what the problem is. Your content needs to be all on ONE computer. That is the only way you can do this.

However, you should be able to update apps on the second machine by entering the corresponding iTunes ID and password. I have done this many times before and never encountered a problem. If it does not update, maybe post the error message you get so it's easier to figure out.
 
okay, everything is starting to get wonky...

i only have media on my main mac. i authorized and downloaded previously downloaded apps onto my imac at work (secondary). i synced the iphone on the secondary to grab the contacts from my iphone.

now,

i see apps that need to be update in itunes at both computers. however, i'm not able to update it on either machine. when i hit "download all free updates" it shows me "accessing itunes store" for a few seconds and then nothing. no error message.

i feel like i'm going crazy. on my main mac, i deauthorized all computers. still i cannot update the apps. i googled & mroogled, but the closest problem others have gives the error 1004. i don't get such errors... it would be helpful if it did.

i'm almost at my wits end with itunes...

***update
so it turns out that the "download all free updates" button may be broken. i was able to update by hitting the "get update" button next to the icon.
but "itunes persistent id cloning" issue still remains. i can't get the secondary mac to take the main macs itunes id.
 
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It is possible (and probably safest) to sync some things to one compute, and others to the other computer, i.e., your music/photos to one and apps to another - which i do easily by clicking "manually manage..."

I sync my apps at my work PC in the office, and all media content to my home Mac.
 
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