The disk utility in OS X is ok at fixing small things but when it comes time for the big guys you need to have Disk Warrior and TechTool Pro. (in that order)
What you are looking at is directory damage and the absolute best tool to fix that is DW. That is its sole aim in life, its reason for being. It repairs directory damage.
www.alsoft.com will set you on the right track to buy or your favorite on-line catalog store.
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I just verified my HD, and it said that it needed repair. Here's the log:
Feb 5 00:56:40: Disk Utility started.
Verifying volume ?Macintosh HD?
Checking HFS Plus volume.
Checking Extents Overflow file.
Checking Catalog file.
Illegal name
Checking multi-linked files.
Checking multi-linked files.
,0)
Checking Extended Attributes file.
Checking volume bitmap.
Checking volume information.
The volume Macintosh HD needs to be repaired.
Error: The underlying task reported failure on exit
Disk Utility stopped verifying ?Macintosh HD? because the following error was encountered:
The underlying task reported failure on exit
1 HFS volume checked
Volume needs repair
So, the button is grey and I can't repair it. Everything seems to be working fine, surprisingly. Any ideas? I'm running Mac OS X Tiger 10.44, on a Mac Mini. Thanks.

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