That depends on how comfortable you are, and also how good you are, at picking apart some of the Unix level log files that MAY (and I stress MAY) offer some insight.
Otherwise, I would suggest that it is some program you have installed. What program it is will involve a lot of tedious trial and error, but I would start with any older programs. Especially any PPC programs you may have still. Those are probably more likely than the rest, but it's no guarantee.
Hello.
Both my portable Macs, a White MacBook 4.1 and a new MacBook Pro, running Snow Leopard 10.6.8, just refuse to Shut Down. After I give them the Shut Down command, they sure quit all the programs, go into the blue screen with the little whirling circle underneath, and they stay like that forever; that is, until I have to press the on/off button for 5 seconds.
I have run DiskWarrior and fixed Permissions on both. To no avail. Some 2 months ago I had the same issue with the MacBook, and had to erase the hard disk, install Snow Leopard anew, and then manually install each and everyone of the programs. Well, it worked for three months...
Sure, I migrated my MacBook info into the MacBook Pro, so that explains part of the problem, but isn't there a way to find out what is causing the problem?
Thank you very much for any and all help.
Cinetuous

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