Mac won't boot up after latest security update

[Terry65]

this has happened before, but there has got to be a way to repair it without days in the shop and another day getting things running right again.

I downloaded the latest security update and when I restarted, the mac never rebooted. I can boot from a system disk and verify that the drive is still good. However, it appears that my permissions are really messed up.

This happened about six months ago and it was also right after an update. I work in design and am not that great with the tech side of the mac (not as good as I should be) but this has got to stop.

What is messing up the permissions and not allowing me to boot?

[hayne]

Please tell us why you think the "permissions are really messed up".

When you booted from the Install DVD, did you run "Disk Repair" in Disk Utility? Did it find anything in the filesystem that needed fixing?

And please tell us what model of Mac you have and what version of OS X.

[Terry65]

thanks for you reply. i only said that about the permissions because I took it into the shop the last time it did it and that is what they said about it. I am running a G4 with Tiger 10.4.11.

When I ran disk permissions, it gave a fairly long list of permissions fixes. I also verified the disk and it checked out fine. My data is not harmed, but it won't boot to the start up disk.

Earlier in the day, I had shut down the computer and it started up fine. It was only after I ran the latest security update (software update runs weekly) that it failed to locate the system disk and restart.

I don't have applejack installed, but have heard it is good for such things.

[hayne]

Quote: Originally Posted by Terry65 I am running a G4

There are many Mac models that have a G4 processor. If you could tell us the specific model, it might be useful.

Quote: When I ran disk permissions, it gave a fairly long list of permissions fixes.

That is usual. Permission repair is not usually useful unless you know (from other symptoms) that the problem is permission-related.

Quote: I also verified the disk and it checked out fine.

So you used the "Verify Disk" button in Disk Utility?
That's good, but in general it is better to use the "Repair Disk" button. This will try to fix any filesystem problems, not just detect them.

I'd still recommend restarting from the Install DVD and then doing "Repair Disk" from the version of Disk Utility that is available from one of the menus there. Does it find anything to repair?

Your final resort would be to an "archive and install" from the Install CD/DVD being sure to select the option to preserve users.
(See this Apple doc: http://docs.info.apple.com/article.html?artnum=107120)
This will keep all your user files and just replace the OS X system files and applications. You should run Software Update afterwards to get your system up to date again.

(But do the "Repair Disk" beforehand in any case.)