How can I easily migrate all my iTunes songs and artists to a new MacBook without a permanent external hard drive?

I've not peered into it deeply, but I imagine that system migration is primarily concerned with copying over the content of your user folder from one system drive to the other. It probably doesn't come with any deeper investigation of what dependencies there might be on additional storage locations.

To move the library easily from one system to another you need to copy both the library database, and the media folder, such that the media folder is at the same path on the new system, or start with the library in a portable shape (the media folder is in the same folder as the .musiclibrary package) that can automatically adjust when opened from a new drive/location. If there is content outside of the media folder this should be consolidated before the migration, or moved to exactly the same paths on the new system so it will be available and can be consolidated later.

The library export functions create text files that list the content of the library. Importing one of these into an empty library only works if every file listed is at the exact path specified, often not the case when the user name on a new machine might be different, or an external drive hasn't been moved over. The new library will, at best, have new date added values for all content. At worst playlists and content will be incomplete or missing because they won't import. When the library is moved correctly nothing is imported or exported, the library database is accessed on the new machine, and if the media is where it is supposed to be it all just works. If the media isn't in quite the right place it will be listed in the library, but won't play. There are ways to fix that, either by moving things around a little, tweaking a preference file, or using a script to effect repairs. We can cross that bridge if we get there.

Once the library is working on the new system, and presuming you have enough space on the internal drive(s), we can talk further about how to consolidate the media into the traditional path of ~/Music/Music/Media so that the library isn't dependent on the external HDD.

tt2

Your music isn’t stolen — your library folder structure wasn’t transferred properly. Moving only the files breaks Apple Music’s ability to track them.

Fix: Move the entire iTunes/Music library folder, then open Music.app while holding Option and choose that library. This restores all your music, artists, playlists, and artwork without a subscription. If your library is damaged, use PowerTunes to rebuild it cleanly.

As for what holding down the Option key is all about see Use multiple libraries in Music on Mac - Apple Support. Unlike most applications you cannot simply double click on a Music or iTunes library file and expect the app to open with that file, instead it opens with the last library it successfully opened. This might even be the copy in the trash if you tried deleting that and copying your old library into the ~/Music/Music folder. Holding the Option key down at launch time is what gives you the ability to switch between libraries, create a new one, or open a library at non-standard path, something you might need to do after moving the library to a new computer.

I see you've just posted while I was writing the above. To be clear I haven't yet asked you to use the hold-option-method to switch libraries. You only do that if you need to. When you make a new library it will be empty, apart from your unhidden iTunes purchase history. Your old library is likely still there if you swap back to it. If you are running Catalina or later then you should be using Music rather than iTunes. Music uses the .musiclibrary package to store the library. The library database is distinct from the media on your computer. The library is an index of all of the items added to it, along with any playlists you have created.

tt2

Without already knowing specific details of your system I'm trying to provide a more generalised set of instructions that you or anyone else could adapt to their own circumstances. If you want me to give step by step advice then I will need details.

1. On the computer that has your working library now what is the path to the active .musiclibrary package that you are using. This is normally ~/Music/Music/Music Library.musiclibrary. The package gets updated every time you do anything will the library so you should be able to check which is it is. If you are not sure search the entire computer for all .musiclibrary files and compare dates.
2. With the library open look under Music > Settings (or Preferences) > Files and note the location of the Music Media folder.
3. Are you certain that everything connected to the library is in the location you found for 2?
4. How big is your library? Use View > Show Status Bar if not already present.
5. How big is your external drive? How much free space does it have?
6. How big is the internal drive on the new computer? How much free space does it have?

tt2

See also Move your iTunes/Music library to a new computer - Apple Community.

tt2

Follow up questions.

1. What version of macOS is on the 2010 Mac Pro? Presumably this is running iTunes with an old version of your library.
2. What version of macOS in on the 2018 MacBook Pro? If running Catalina or later you should be using Music on it, and in general you don't now want to open older .itl files on it, though there could potentially be specific circumstances when you want to do this, if for example you know that one of those libraries held more content than is currently listed in Music.
3. What version of macOS is on the 2020 MacBook Air?

I understood that you wanted to copy the library from the 2018 model to the 2020 model? Why did you make any changes to the old library? A key part of cloning a library to a new system is not to make any changes to the old one.

tt2

~ is the standard Mac shorthand for your user's Home folder. For example on my M1 MacBook Air running Tahoe, where the system drive is named Tahoe, this folder translates to /Tahoe/Users/steve as steve is my profile name.

~/Music is the default location for music related things in your user profile. In the past the main iTunes folder would be placed here, e.g. ~/Music/iTunes. From Catalina onwards this is also where the (Apple) Music (app) library gets placed so that its default location is ~/Music/Music. On all Mac systems you also have the ability to open or create a library at some custom path by holding down option as you launch either iTunes or Music and using the choose/create library dialog. In principle Music should be able to open and convert .itl files created by iTunes, but in practice not all versions of Music can do this, and not all .itl files will be compatible when it can.

A Music library database is in the form of a package (similar to a zipped folder) normally called Music Library.musiclibrary. If you've been using Music at all then there must be a .musiclibrary package somewhere that you've been accessing. Music cannot update .itl files. Some versions of Music (e.g. Monterey) cannot even convert .itl files into the .musiclibrary format. I can, if needed, convert a valid .itl file into a .musiclibrary package using a combination of the Mojave version of iTunes (for iTunes libraries that predate Mojave) and the Catalina version of Music, yielding a .musiclibrary package that will open in any version of Music. Check my profile for my email address if you need this help.

My impression from your earlier posts is that you have at some point had a working Music library which it would be good to go back to, however if that isn't the case then it should be possible to take your .itl file and convert that to the .musiclibrary format for use with Music in a newer version of macOS. For the converted library to work your media will also need copying into whatever location the library expects to find it. For a library originally built in iTunes this is often ~/Music/iTunes/iTunes Media or ~/Music/iTunes/iTunes Music, but if you had consolidated to an external drive at some point then it would be your chosen path on that drive. Once you have a library that at least opens in Music and displays some content it is then possible to drill down to the properties of a track and check where the library expects to find it via the Get Info > File tab. If/when you get to the point where you have a working library that has the content you want in it but is still dependent on an external drive when you don't want it to be, we can discuss how you move the active parts of the library onto internal storage. There is an overview here Managing your Mac media libraries - Apple Community which I can turn into specific advice if I know relevant details about your system.

tt2

JIH69 wrote:

I know I'm crying in my beer. for extra help, but what the heck are some folks saying to 'hold down option key' when opening music (on the 2020)? Do I hold down same key when I plug in to 'itunes' on old machine?

Holding down the Option key when launching iTunes (pre-Catalina), or Music (Catalina and later), brings up a dialog where you can create an iTunes/Music library – or choose which existing one to use as the current one.

The Option key performs a similar function for the TV app (Catalina and later), and for iPhoto/Photos.

Whether you would want to create a new library in a different location, or to have multiple libraries, might be a separate matter. But this is what the Option key does.

It sounds like you're trying to copy a large iTunes Library from a machine running High Sierra (or something else earlier than Catalina) to a new machine running Sequoia or Tahoe.

I do not know if either Migration Assistant or Music know how to automatically "migrate" a music library forward when you are jumping that many macOS versions at a time. When I replaced a Mac running High Sierra with one running Ventura, I put a copy of my iTunes Library on an external SSD, and built Music and TV libraries there, out of necessity (not enough free space to do this on the internal drive).

Music did not seem to want to import my iTunes Library as a library, so I did an Import and pointed it at one of the top-level folders within the copied iTunes Library to let it reimport the songs.

Unfortunately, the resulting Music Library had many huge holes in it. It appeared that specific albums would either make it entirely, or not make it at all. An educated guess is that Music built a big list of all subdirectories within the directory that it was told to import. A big list that it silently truncated (buffer overflow) before importing the music mentioned in the first part of the list without incident.

Since I had not deleted the iTunes Library, I went back and did many smaller imports of a few albums at a time and recovered the contents of the library in that way.