access denied error message

Hi G_andy, and a warm welcome to the forums! 🙂

Could be many things, we should start with this, even though you have done some of it...

"Try Disk Utility

1. Insert the Mac OS X Install disc that came with your computer, then restart the computer while holding the C key.
2. When your computer finishes starting up from the disc, choose Disk Utility from the Installer menu. (In Mac OS X 10.4 or later, you must select your language first.)
*Important: Do not click Continue in the first screen of the Installer. If you do, you must restart from the disc again to access Disk Utility.*
3. Click the First Aid tab.
4. Click the disclosure triangle to the left of the hard drive icon to display the names of your hard disk volumes and partitions.
5. Select your Mac OS X volume.
6. Click Repair. Disk Utility checks and repairs the disk."

http://docs.info.apple.com/article.html?artnum=106214

Then Safe Boot from the HD, (holding Shift key down at bootup), run Disk Utility in Applications>Utilities, then highlight your drive, click on Repair Permissions, reboot when it completes.

The usual reason why updates fail or mess things up, is if Permissions are not fixed before & after every update, with a reboot... you may get a partial update when the installer finds it doesn't have Permissions to change one obscure little part of the OS, leaving you with a mix of OS versions.

Some people get away without Repairing Permissions for years, some for only days.

If Permissions are wrong before applying an update, you could get mixed OS versions, if Directory is the slightest messed up, who knows!

If many Permission are repaired, or any Directory errors are found, you may need to re-apply some the latest/biggest updates.

May even need to do an Archive and Install if you have room on the HD...

http://docs.info.apple.com/article.html?artnum=107120

I only use Software Update to see what is needed, then get them for real via...

http://www.apple.com/support/downloads/

That way I can wait a week or so, check the forums for potential problems, and get Permissions & such in order before installing.

Might also see this...

http://www.thexlab.com/faqs/repairprocess.html

Or try this...

applesetupdone...

http://discussions.apple.com/thread.jspa?messageID=6059333&#6059333

http://www.askdavetaylor.com/howdo_i_reset_my_mac_os_x_admin_rootpassword.html

This was Posted by: JoseAranda at September 9, 2006 3:48 AM

"OK, restart your computer, hold down Command-s and type in the following:
/sbin/fsck -fy Enter
/sbin/mount -uaw Enter
rm /var/db/.applesetupdone Enter

1. The rm command is the remove command which deletes the file.
2. Robert: I'd rename the file via: mv /var/db/.applesetupdone /var/db/.applesetupdone.old

reboot Enter

Once you've done that the computer reboots and it's like the first time you used the machine. Your old accounts are all safe. From there you just change all other account passwords in the account preferences!!
end of posted by: JoseAranda"

Hmmm, do you have access to another PPC Mac to try FireWire target disk mode...
http://docs.info.apple.com/article.html?artnum=58583

I'm just about to zero the drive and start again.

might be a good idea, starting from scratch. Then do a "combine" update and see where your at before anything else.