When I open iTunes on my new computer using the .itl file, and using the same external drive holding the songs, all of the songs I added to iTunes up to a certain date have broken links, while none of the songs have broken links on the old computer.

Question

I want to open the  iTunes library on my new laptop with all the playlists and stuff I built on the old computer. I have all my music on an external drive. I have copied the .itl file from the old computer and opened it on the laptop, and it has all the playlists, but all of the songs that were added to iTunes up to a certain date have broken links. What am I doing wrong?

Answer 1

Moving library files around while leaving the data in the same place usually presents no problems. Moving the data around independently from the library usually breaks things. With Windows machines all you should need to do is make sure that the same drive letter is being used on the new system as with the old. If that is not possible you need to get your library into a portable layout before moving it between systems.
Typical layout of iTunes folders:
When the media folder is inside the main iTunes folder as shown above then the library is portable. Typically with a split library the iTunes Music or iTunes Media folder (everything inside the red outline) is moved to a different drive by choosing a new locaton for it and then consolidating.
To make the library portable again you need to copy the library files and album artwork folder into the parent folder of the media folder so that the nested relationship is recreated. (BTW If your media isn't already inside your designated media folder then you will also need to consolidate the files that are outside of it, before you copy the library files.) You can then use the hold-down-shift-when-starting-iTunes method to open the library file in that parent folder. Once the library has been opened, tested and closed you are most of the way there.
The iTunes window inherits its title from the folder holding the library files so, unless you created a folder called iTunes to hold the media folder, iTunes may now have an unexpected title when you run it. The parent folder can be renamed as iTunes, and the library opened again. Alternatively, if the parent folder is at the root of the drive, or has other data which you wish to leave in place, you can create a new top level folder called iTunes and move the library files, album artwork and media folders into it before opening and testing the library again.
If the library doesn't work after any step simply reverse it by undoing a move or rename or opening the previous set iTunes Library.itl file.
If all has gone well then the library is now portable. Once you've migrated the data to a new system you can copy the library files back to their usual internal location if you find that having them on the external drive affects performance...
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