Syncing to new computer: iTunes threatening app data wipe

Instead of transferring backup files, I just backed up my iPhone using iTunes on my laptop. A backup is a backup, so I don't think this should affect anything.

I did not transfer the iTunes database file you mention, instead I just used "Home Sharing" to transfer my purchases to my laptop and authorized the "new" computer in iTunes. My content is all there, fully playable and working as it should.

The main problem here is syncing with iTunes on my "new" laptop without my iPhone wiping my app data and settings. My iTunes library is authorized and so far I've only used Apple-approved methods of transferring my iTunes data.

I wish I could just backup my iPhone and test it out myself, but since backups don't include game data either, I'm still kind of stuck.

I understand, I'll try that out. Thanks!

Wow Katrina, your advice worked perfectly:

First I'll recap what my two computers looked like before I started anything:

On my desktop, I had iTunes working perfectly with all my music, movies, and apps. My laptop had the same content as well (transferred from my desktop via the "Home Sharing" feature of iTunes) but the metadata (star ratings, etc) was missing, as Katrina anticipated it would be.

To start, I tried replacing the "iTunes Library.itl" file (located in C:\Users\username\Music\iTunes) on my laptop with the one from my desktop. I started up iTunes but pretty much all of my content was missing; the attempt was a failure. I un-replaced the .itl file and iTunes looked normal again. Considering the libraries between the two computers weren't exactly the same from the start, there was no way this would've worked anyway, I just figured I'd give it a try.

I then tried Katrina's suggestion of copying the ENTIRE "iTunes" folder (located in C:\Users\username\Music) on my desktop and replacing the "iTunes" folder on my laptop with it. This worked perfectly. I fired up iTunes, my library popped up with all metadata intact, and when I plugged in my iPhone the sync proceeded exactly like it does on my desktop, no popups whatsoever. My desktop PC even showed up in the "Shared" section of iTunes since I had Home Sharing on. Everything just works.

After syncing my iPhone with my laptop, I checked the games on my iPhone and all the save data was preserved.

I can now sync my iPhone to my laptop without any problems, exactly like I used to on my desktop PC.

Thank you Katrina S! Your advice saved me hours of scouring forums. It turned out the solution was simpler than I expected.

(iTunes 10.1.1.4, Windows 7 Ultimate, iPhone 4 running iOS 4.2.1)

For me Home Sharing was pretty quick, but because files transferred that way don't retain their metadata it wasn't the best solution in this migratory situation.

Response to edit: I'm not quite sure what you mean by "other" app folders. I pretty much just replaced the entire "iTunes" folder on my laptop with the one from my desktop and it worked great. The "iTunes" folder contains the subfolders you've already mentioned: "Album Artwork, iTunes Music, Mobile Applications, Previous iTunes Libraries" and the following individual files: "iTunes Library Extras.itdb" "iTunes Library Genius.itdb" "iTunes Library.itl" and "iTunes Music Library.xml"

Once the desktop "iTunes" folder was placed in the correct spot and the old laptop "iTunes" folder was deleted, the whole thing worked perfectly, metadata fully intact.

Okay I understand. You are correct, I did not have to mess with any of iTunes' file structure in the "AppData\Roaming\Apple Computer" directory. Simply by swapping out the folder located at "C:\Users\username\Music\iTunes" my entire problem was remedied.

And yes, iTunes did allow me to back up my iPhone (without syncing it) both before and after I fixed the .itl file issue.