I didn't have a problem with Snow Leopard and my prior printer, but our elder MacBook (plastic, dual USB, no ML support) running Lion is having repeated problems with our Brother HL-6180DW. The printer keeps going into a paused state (sleep / wake bug?), and users are prompted to "Type the name and password of a user in the lpadmin group to allow...". Of course the kids don't know what to type -- and this is a very awkward prompt in any case. Something is broken.
Of course a lot of things are broken with OS X and printing - even in Mavericks. So this isn't a great surprise. It is annoying though.
There are lots of online tips on this mostly focusing on terminal commands for adding users to lpadmin manually or disabling printer queue password requirements. Sometimes they seem to work, sometimes not. .
The only Apple doc on this covers 10.5 (Leopard) to 10.6 (Snow Leopard). It's weirdly written, and suggests some intersection with parental controls "Limit printer administration" (which makes sense). Then it talks about toggling admin privileges for the admin user, even though one assumes that only non-admin users would see the prompt.
FWIW even after I created a new admin account on the Lion machine OS X 10.7 wouldn't let me toggle admin status for my primary admin account. It merely said it couldn't. Seems there was something odd about that admin account. So I deleted it (my admin accounts are all disposable, I only use them for admin tasks). I'll see if fixing that makes any difference. If not I'll play around with toggling parental controls and exploring Workgroup Manager and those terminal commands.
- fn -
 If you don't like Terminal Commands took a look at Workgroup Manager. Lion’s Server Admin Tools includes Workgroup Manager, I used Workgroup Manager downloads to get the Mountain Lion version (see also). You need to select “Show System Records” to see the “system” users and groups (thank you Google).
In Mountain Lion the lpadmin group is _lpadmin and the Name is Print Administrators. All Administrators were members of lpadmin, and so was ONE of the FIVE non-admin accounts on that machine. Interestingly the ONLY non-admin member of lpadmin on my ML box has parental controls enabled. By Darwin, Apple made such a mess of permissions in OS X.
- 10.5: Disable printer queue password requirements - Mac OS X Hints: first seen in 10.5, Leopard.
- Mac OS X - Print Job “On Hold (Authentication required)” - Authentication problem with print servers, suggests I might try changing his password.
- osx - How to Resume a Paused Network Printer with non-Admin credentials?: “_lpoperator should suffice, talks about adding Staff to _lpoperator
Most of the problems were with one user’s account. With Workgroup Manager I found he was NOT a member of Staff, but all other Lion user accounts were. He was a member of a Group that had the same name as his User Name, probably due to the horrid User/Group/Staff mess of 10.3 to 10.7. I deleted that Group and assigned him to Staff. I’ll see if that works.
There’s also a recent Brother printer driver update to try, and a firmware update. The latter requires Java, which is essentially obsolete on the Mac. I was able to perform the update using an old Lion machine. Shame on Brother for not supporting firmware updates via the web app. (They used to.)