Submit Hint Search The Forums LinksStatsPollsHeadlinesRSS
14,000 hints and counting!

10.3: Make iTunes available to all in multiple users mode Apps
When you use the new multiple users feature in Panther, you may run several user sessions, each with its own copy of Finder, TextEdit, whatever, except iTunes: the system prevents user B from opening iTunes if it is open in user A's session. Very annoying.

Fortunately you can override this behavior (with no apparent damage) as follows:

  1. quit iTunes.
  2. locate the iTunes application in the Finder, then control-click and select Show Package Contents from the contextual menu.
  3. in the "Contents" folder, locate the "Info.plist" file; duplicate it (in case you make a mistake), and then open it in TextEdit (or Property list editor if you installed the Developer Tools.
  4. locate the LSMultipleInstancesProhibited key: it looks something like this (at the end):
  5. now change the word true to false (leaving the brackets, of course!), and save the file.
  6. open the /Library/Cache folder (from the root directory, not the current user's one); if there are some files with names beginning with "," then trash them (the Finder may ask for your password).
  7. restart the computer.
Now you can launch iTunes from the first user, log on as another user, and launch iTunes again. Note that only the current one will actually play music, fortunately!. This seems to work with no hitch, so I dunno why it has been disabled by Apple.

[robg adds: I haven't tested this hint, and I tend to think Apple disabled the multiple instances setting on purpose, so I probably won't switch mine ... if you try this hint, I'd strongly recommend having a good backup of your iTunes Library file, just in case something goes wrong. A previous hint discusses ways of quitting the other user's iTunes as a workaround...]
  • Currently 2.57 / 5
  You rated: 4 / 5 (7 votes cast)

10.3: Make iTunes available to all in multiple users mode | 16 comments | Create New Account
Click here to return to the '10.3: Make iTunes available to all in multiple users mode' hint
The following comments are owned by whoever posted them. This site is not responsible for what they say.
10.3: Make iTunes available to all in multiple users mode
Authored by: magir on Jan 14, '04 02:29:33AM

One reason why apple disallowed it could be the iPod. When two people have iTunes open and an iPod is mounted, both iTunes might try to open the library which can result in data loss. It's possible that one is in read-only mode, but I haven't tried it. Another issue is Rendezvous sharing.

[ Reply to This | # ]
10.3: Make iTunes available to all in multiple users mode
Authored by: jimlaurent on Jan 14, '04 08:07:07AM

While this may work for playing music (read-only) it's hard to tell what might happen when the second user adds a song to the libarary. Does the first iTunes have a file open that the second instance will change on the fly.

Essentially this appears to be a crude DB locking implmentation to prevent corruption when addin to or modifying the library.

[ Reply to This | # ]
It's not about sharing a library, it's about accessing your own library
Authored by: hamarkus on Jan 14, '04 02:38:24PM

It's not about sharing a library, it's about every user accessing its own library. At least, that's how I understand the hint.

One reason why Apple might have disabled it, is the library sharing problem, if two instances of iTunes are running, Rendezvous would have to share two libraries over the subnet. Rendezvous works on a computer basis not a user basis it probably could not share between two users on the same computer.

If two instances of iTunes would access the same library, the situation is naturally more difficult.

[ Reply to This | # ]
10.3: Make iTunes available to all in multiple users mode
Authored by: PsychoSpunk on Jan 14, '04 08:59:34AM

When I first encountered it, I realized it was disabled for sharing purposes. Each instance is a separate process which will attempt to bind to the port used for sharing. Only the first process will be bound, and the remaining ones will be unable to be shared.

[ Reply to This | # ]
10.3: Make iTunes available to all in multiple users mode
Authored by: houchin on Jan 14, '04 08:36:33AM

As of late last week, there's actually a better solution (although I haven't tried it yet).

iTiR - iTunes interuser Remote

This software claims to be able to let you run iTunes in one user but control it and listen from another user

[ Reply to This | # ]
10.3: Make iTunes available to all in multiple users mode
Authored by: kevinv on Jan 14, '04 09:53:48AM

Another reason is that sounds from both sessions can play through the speakers (at least it could on the first 10.3, not sure about the updates). Kind of pointless that. Hmm, possible to have a script run on session change to pause one player?

[ Reply to This | # ]
10.3: Make iTunes available to all in multiple users mode
Authored by: SOX on Jan 14, '04 12:47:42PM

All sounds are hushed when you do a fast user switch so that's not an issue.

[ Reply to This | # ]
10.3: Make iTunes available to all in multiple users mode
Authored by: paulio on Jan 14, '04 11:15:21PM

> All sounds are hushed when you do a fast user switch so that's not an issue.

My memory of the 10.3 beta was that iTunes played in the background after a switch to another user. I was so disappointed when I realized that the release version stopped playing after the switch.

[ Reply to This | # ]
10.3: Make iTunes available to all in multiple users mode
Authored by: teach on Jan 14, '04 11:08:50AM

You know, I ran into this same issue when setting up 10.3 at my home. I finally made the leap to this whole crazy "multiple user computer platform" idea. The first thing that I ran into was that my wife's account couldn't access my (OUR) iTunes library.

Apple does have a document on how to work around the issue without any hacks:

Apple Article ID: 93195 - 11/10/03
TITLE: iTunes: How to Share Music Between Different Accounts on a Single Computer

[ Reply to This | # ]
10.3: Make iTunes available to all in multiple users mode
Authored by: Quantum Panda on Jan 19, '04 05:30:43PM

Gee, I figured that process out more than a year before Apple originally created that document. If you have a real understanding of the operations of a multi-user OS, it becomes obvious that for multiple users to share a music library, it has to be stored outside of a specific user's protected space.

What's still missing is the ability to fully share one library among all the machines on a local network. The existing iTunes Sharing feature is a step towards that, but it suffers from what I consider to be two major limitations/drawbacks: iTunes has to actually be running and sharing on the machine where the music is stored, and no tag information can be modified from the guest machine (which is primarily of significance for ratings and play counts).

The first limitation means that in order for me to listen to my music from my iBook, I have to be logged in on the desktop machine and iTunes has to be running; there is no way to access that music through iTunes Sharing if no one is logged in on the host machine. (And iTunes distinctly does not like having its Music Library located on a remote volume--I've tried.)

The second limitation interferes with my preferred listening habits. Approximately half of my library is still unrated (because those files were all ripped long before iTunes supported ratings), so I try to spend some time each day listening to the unrated tracks to assign them ratings. Since I can't set ratings from the guest machine, I have to spend that time actually at the desktop machine, which often will interfere with other tasks I'm trying to do (tasks which are one of the reasons I bought the iBook in the first place). And play counts are not updated for shared listening, so Smart Playlists I have that are based on play counts won't know that I listened to those tracks.

I suppose Timbuktu would be a solution to the second problem, but it's far too pricey to purchase just for that. There isn't really any security or piracy problem inherent in allowing the owner of the shared files to choose to allow the play counts to update for files played by guest users, except what is already inherent to the concept of the sharing itself. In my case, since I don't have the iTunes Sharing port forwarded by my router, no one not in my household is going to be listening to my music anyway (and, if I were running iTunes 4.1 or later, the program itself would disallow that), so for play count purposes, my listening remotely is just as valid as listening locally.

As for the first problem, even Timbuktu wouldn't fully solve that, because you still have to log in to launch iTunes, even if you're logging in remotely via Timbuktu. I ought to be able to launch iTunes for sharing purposes only as a background process not tied to a specific user.

[ Reply to This | # ]
10.3: Make iTunes available to all in multiple users mode
Authored by: lstewart on Jan 14, '04 11:32:58AM

You know, back in iTunes version 2 and earlier, the software behaved kind of like this all the time. I don't know if the setting itself existed--probably not--but iTunes allowed multiple instances of the software to have the library open at the same time.

For instance, I had both our Macs networked, and aliases set up so that both of them accessed the same iTunes library on one of the machines. It was pretty slick.

Write contention was handled like this: the first machine to open the iTunes library (Machine A) had it write-locked, and the second one (Machine B) had it read-only. If iTunes on Machine B made a change to the file, it would create its own copy of the iTunes library (called iTunes Library 2) in the same folder, and make its edits in there. These edits, to my knowledge, would NOT be assimilated or merged back into the original library, so this was an easy way to get things out-of-whack.

I suspect maybe it still works the same way. So if you do this, please be aware that you should only make changes to the iTunes library from the account that first opened iTunes!

[ Reply to This | # ]
10.3: Make iTunes available to all in multiple users mode
Authored by: ericdano on Mar 06, '04 12:51:28AM

Yeah. I am trying to set up a server that will allow for multiple computers to access the same set of music and iTunes library. Actually, which ever computer quits LAST seems to overwrite the Library files.

[ Reply to This | # ]
what a giant snarl!
Authored by: SOX on Jan 14, '04 12:55:03PM

If you read apples support article on the topic of shared itunes library you find it also mentions that

"Note: If multiple users of a computer are storing music in one folder, duplicate song files are generated when a user imports music from CD that has already been imported by another user."


For home use I just want to have all of our music in one library. Sounds like you have to be really attentive about who is adding music or you can get dupicates. I'd prefer just to use smart playlists to keep our own sub collections if we want to.

[ Reply to This | # ]
Works For Me
Authored by: schneb on Jan 15, '04 12:19:25AM

This was a big problem for me. My wife would have it open on her side and I could not open it on my side. I followed the directions and no longer have that problem. All of our music has already been processed and resides in a shared folder, so no problems at all.

I love it! Great hint. All original files have been backed up just in case I want to revert.

[ Reply to This | # ]
10.3, 10.2: Make iTunes Library Shared (better than Apple)
Authored by: jwoolson on Jan 15, '04 12:20:01AM
This doesn't apply to being able to *launch* iTunes, it is how to *share* the music from one library to all users.

This tip works best if you set it up BEFORE you start adding music to anyone's library. This will share the music files and Library XML file, but it won't help resolve the iTunes Music Store ID conflicts, nor will it let you launch iTunes without using the tip at the top of this thread.

1. Pick one of the User's Music folder to be the Master Music Library.

2. Set the priviledges of that Music Folder to read/write for All Users and move it to a shared location such as /Users/Shared/.

3. Create a symbolic link (not an alias) of the /Users/Shared/Music folder within each User's folder /User/[theusername]/Music

4. Repeat symbolic link for each for the remaining users so that every user has a symbolic link, i.e.: /Users/Shared/Music folder -> /User/[theusername]/Music for all users.

This will not require any changes to iTunes' Preferences and it will let each user access the same music library. There won't be any duped music because iTunes will check for dupes when you import music while logged in as any of the users.

It gets a bit messy if you want to combine all the various users' music libraries into the single library. The principle is that you'll have to drop the second, third... users' Music folders into the master library, but it will discard Star Ratings, etc.

Jonathan Q. Woolson
Louisville, CO 80027

[ Reply to This | # ]

10.3: Make iTunes available to all in multiple users mode
Authored by: DougAdams on Jan 16, '04 12:45:21PM
Check out this article as well: Share Libraries Among Multiple Users.

[ Reply to This | # ]