Sunday, September 14, 2008

OS X Leopard 10.5: The unknown user and group bugs

I waited quite a while before upgrading to Leopard (OS 10.5). I knew the OS had had a turbulent childhood, so I waited for 10.5.3. Even so, I've run into two ugly and common bugs and one weird and exotic one:
Now I'm on common bug #3. After upgrading from 10.4 (Tiger) to 10.5 (Leopard) an "unknown user" and/or "unknown group" appears in every user account when viewing sharing and permissions. It will also appear in the file sharing preference panel. It can be removed from the preference panel, but there's no proven safe method to remove this "user" from the OS. I've reviewed a number of web postings on this and related topics:
After reviewing all the references, and the wars about which unix comands might help, I have these tentative conclusions:
  • this was a very bad bug prior to 10.5.2, but after 10.5.2 it's supposedly a cosmetic problem
  • Apple made big changes to how permissions work in 10.5 (but "repair permissions still finds "problems" right after an OS X archive and install, so they have work yet to do somewhere), that led to this problem.
  • Anyone who used Netinfo to create shares or used SharePoints in 10.4 or earlier might have extra problems.
I'm going to leave this bug alone and see if 10.5.5 does some clean up. In addition to being an annoying blemish it is the sort of defect that comes back to bit us in combination with another bug or future update. There's a rumor that after a year or so repeated train wrecks (MacBook Air, 10.5, iPhone 2.0, MobileMe) Apple may decide to focus on quality. So maybe they'll get around to cleaning up this icky one.


Update 3/11/2010: Apple never did clean up 10.5. By the time I migrated the 10.5 accounts to a 10.6 machine the permissions were a mess. I think Apple shafted us with this particular bug. In 10.6 one can delete the unknown user.

5 comments:

boz said...

I was also having the "problem" with (unknown) user showing up in the Sharing & Permissions pane of my Macintosh HD info - with full read & write permission. I could not change nor delete (unknown). Cosmetic or not, I wanted this gone. I have checked these forums, blogs, and other help sites for months and found nothing that worked for me - no Terminal commands, nothing.
Until today. And I happened on this fix totally by accident. Even now, I have 9 tabs open looking for a solution. In the Sharing & Permissions pane, the user "Everyone" had Read Only permission. I changed that to No Access and *(unknown) disappeared!*
I hope this works for you.
bz
PS - I posted this in the Apple Discussion thread where you linked to this blog.

Jobauma said...

It was only a moment ago I got this problem too, really annoying stuff, but then I was so lucky to find this page.

Thank you so much!

Anonymous said...

Found this unknown user group after downloading a couple of folder icons and used the tip discussed in this blog and presto... deny access to everyone and unknown is gone.

Anonymous said...

Found this unknown user group after downloading a couple of folder icons and used the tip discussed in this blog and presto... deny access to everyone and unknown is gone.

Anonymous said...

DO NOT deny access to everyone it totally screwed up my drive and it became unaccessible