Sharing & Permissions unknown user

Hi,

When i check the information on a file or folder (any) with command-i, i see the usual list:
Jay (me) - Read & Write
admin - Read & Write
everyone - Read Only

But there is another one there that i have never seen before:
_unknown - Read & Write

I can't remove it and i have no idea where it came from.
It's there in every file and folder i checked throughout my harddrive and i know for sure that it was not there in previous versions of OS X. I don't know if it's 10.6 related but i noticed it first about 2 weeks ago.

I believe the _unknown user is the cause of hundreds of "ACL Found but not expected..." messages in Disk Utility when i check the permissions.

Any suggestions on how to get rid of this?

Thanks,

Jay

MBP 17" 2.6GHz Hi Res, 4GB RAM, 500GB // Apple since '98., Mac OS X (10.6.2), "Always make backups!!"

Posted on Jan 7, 2010 1:47 AM

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Posted on Jan 11, 2010 5:23 PM

Yesterday i found myself with a crashing finder every time i ejected an external drive, my sound was on the fritz and apps kept crashing. Cause unknown.
I wiped the drive and re-installed a clean OS.
I could not import my account from the setup assistant after re-install because the backup was 10.6 and the clean install was 10.5, so i had to create an account to update and install 10.6.
At that point i could import my old account but figured... that way i would get the same problem again with my old account becoming 502.

So i imported all my files, settings and prefs over manually and everything is working as it should now AND i am 501 🙂

Upon inspection 3 of the 5 partitions still had the _unknown user there and by accident i found the fix:

I added myself with the +, then selected "make jay(me) the owner".
As soon as i did this the _unknown user dissapeared.
I applied the changes to all the enclosed items of that partition and now the _unknown user is nowhere to be found on any of the partitions or files.

Thank you so much for your help, it's folks like you that make this forum worth while 🙂

Jay
35 replies

Jan 10, 2010 5:44 AM in response to KJK555

KJK555 wrote:
I agree, using SL install DVD would be a better choice for dealing with the old "jay" directory.
That actually could be done as the last step.

I would still delete and replace the old jay account though.
Unfortunately, simply changing the UID has broken accounts in my experience.

Chances of getting by without problems by not copying the new basic files to the old
account are good. If you have a bootable or time machine system backup, using migration
assistant to import user account settings would probably be the best bet.

Unfortunately there is no really easy way to replace a corrupt account (if it is indeed corrupt).

there is nothing wrong with the OP's account at the moment. all he wants is to change the UID from 502 to 501 to align with a bunch of files currently owned by UID=501 on various disks. I thought that deleting and recreating the user would work to do this quickly provided it would automatically give the recreated user UID=501. as it doesn't want to do that it's best not to touch it and change the ownership on all those other files instead. that's easy to do on the extra drives. it can also be done on the whole system drive using find but I'm not sure what the exact consequences would be. that's why i didn't want to do it.
I have had the best luck with migration assistant or tediously rebuilding the user directory
from a backup, manually (ouch). One way to preserve your old mail and other apps settings
is to simply trash their directories from the new account before copying over to the old
account. What ditto doesn't see, ditto won't copy.

"sudo dscl . -delete /Users UniqueID 501" is just an extra step that probably won't do anything

the command syntax is wrong and won't do anything as far as I can see.

anyway unless the old account is corrupt. Deleting an account using the system preferences
should completely eliminate the account UID, if it doesn't then there probably is corruption.

again the account is not corrupt so this isn't an issue.
Re creating the account should take care of any temp directory problems.

yes, which is why I wanted to do it that way first too. the problem was the deleting and recreating the account gives the old UID back.
Actually, an OS re install may be needed to straighten it all out.

Personally, I have solved the "unknown user" and "runaway ACL" problem long ago.
I disable (remove) UID 99 and use the old "tiger" (10.4.x) permission structure
(user ID = 501 - Group ID =501):

I would never do that. there is no reason or point in going to the deprecated Tiger group structure. while it's not needed here I've changed a lot of accounts (and helped others do the same) with Tiger group structure to the new system using the first method I suggested earlier in the thread by deleting and recreating the accounts and never had any problems with any of them.
uid=501(kj) gid=501(kj) groups=501(kj),402(com.apple.sharepoint.group.1),204( developer),100(lpoperator),
98( lpadmin),81(_appserveradm),80(admin),79(_appserverusr),75(_sshd),74(mysql),
61(localaccounts),50(authedusers),12(everyone),4(tty),401(com.apple.access_scree nsharing)

Since I have been using the above permission structure, (10.5.2), I have only had the main user
directory crap out on me once, and that was because of a keychain problem.

Jan 7, 2010 1:31 PM in response to V.K.

Hi V.K.
Thanks for the reply.
My harddrive has 5 partitions, every file on every partition has the _unknown user.
Here is 1 example:
ls -lade0 /Volumes/Music/07.\ Mail/Memo.m4a

The only folders that do NOT have the _unknown user seem to be on my OS partition:
Applications
Library
System
Users

These are the only 4 folders that don't have the user.

Jan 7, 2010 2:44 PM in response to jayv.

Pr0digy V. wrote:
Hi V.K.
Thanks for the reply.
My harddrive has 5 partitions, every file on every partition has the _unknown user.
Here is 1 example:
ls -lade0 /Volumes/Music/07.\ Mail/Memo.m4a

please post the output of that command! that's where all the relevant info is.
The only folders that do NOT have the _unknown user seem to be on my OS partition:
Applications
Library
System
Users

These are the only 4 folders that don't have the user.

Jan 7, 2010 11:33 PM in response to V.K.

Hi V.K.

Yes my username is Jay but it has never been changed since the OS was installed.
It's 1 drive with a couple of partitions. One for the OS, one for apps, music etc. Time Machine is external on a FW drive. No other user directories on the other partitions or external drive, on the OS partition just me and a managed Guest account.

Jan 8, 2010 8:43 PM in response to V.K.

V.K.
I followed your instructions to the letter and everything went smooth.
Only when i run the id command now i get this:
id
uid=502(jay) gid=20(staff) groups=20(staff),101(com.apple.sharepoint.group.1),401(com.apple.access_screens haring), 204( developer),100(_lpoperator),98(_lpadmin),81(appserveradm),80(admin), 79(_appserverusr),61(localaccounts),12(everyone),402(com.apple.sharepoint.group .2)

Looks like i am still 502, when i ctrl-click my account there is an option to change the uid, if that a safe way to set it back to 501 ?

Jan 9, 2010 4:10 PM in response to jayv.

aha, that's why it would not give your main user UID 501. it was taken by the test account. ok then. make another admin account. it will get UID=503. then delete test the account testaccount along with its home directory. then redo what I told you to do earlier with user jay. change its home directory from the new test account and delete user jay and then recreate it. it should now be recreated with UID 501.

Apr 10, 2010 3:22 PM in response to V.K.

I had a similar problem to what the OP (original poster) had - _unknown user showing up in my permissions of files in my Macintosh HD (not my home directory), but it was a result of changing my shortname ( http://support.apple.com/kb/HT1428). With the permissions screwed up, programs were crashing (Logic Pro 9) but I was able to partially fix the problem file by manually changing the permissions of files and folders with the DO NOT ENTER logo on them but I unknowingly did use the "apply to enclosed items" option. Now, when I repair permissions on my Macintosh HD in disk utility, I get ACL found but not expected errors. How can I recover from this?

My ultimate goal is to completely eradicate the _unknown user and not have any permissions errors. I know this topic is closed but still any advice?

Message was edited by: BOSSDOGG

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Sharing & Permissions unknown user

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