Its a pain when you either get a new computer or use another computer to sync your device. iTunes only allows one computer to be linked with your device. This is a major flaw in the system as many people have got more than one computer/laptop and cant restore their device every time they connect it to a different Computer.
But no need to worry, we are here to help you! Here’s a tutorial on how to over come this major flaw which apple has made in their system. Remember, even if you don’t have another computer, i advice you to still follow this tutorial and backup the files mentioned in this tutorial for future use.
Step 1: Find the directory called “iTunes”
On most of the operating systems its located in the music folder
For example in Windows Xp, the path is
On the Mac it is in your Music directory
Backup these 2 files to a safe place
a. “iTunes Music Library.xml”
b. “iTunes Music Library” (Tunes Music Library.itl on PC)
These are the files you will be modifying.
Step 2: Download the following software’s that you need for this process and install them.
Step 3. Now Find your iTunes Library ID on the machine your iPhone currently syncs with.
Open “iTunes Music Library.xml” with a text editor and find the entry between the <string></string> tags, after “Library Persistent ID”. In the example below this is 8B6C633F7DACB74B. Copy this entry exactlyto a piece of paper, email, temporary file etc. You can then close this file.
Step 4: On the new machine you want to sync with open “iTunes Music Library.xml” in a text editor. Again, find the entry between the <string></string> tags after “Library Persistent ID” and copy this entry exactly. This time you can use the clipboard if you wish.
After copying, replace this entry with the one you copied in step3. Make sure you do not change anything else, and the length of the entry is 16 characters/digits. Save this file and close it.
Step 5: In the Hex Editor which we downloaded in step 2, open “iTunes Music Library” (Tunes Music Library.itl on PC).
Select “Find and Replace” from the Edit menu. Make sure “Hex” matching is selected (not ASCII). In “Find” enter the ID you took a note of in step 4. In Replace, enter the ID you copied at the start of step 3. Choose Replace All, there should be one match.
Save this file and close it.