Your system or hard drive may be corrupted. Try the following:
Boot from your OS X Installer. Be sure to use the installer for the version of OS X you have installed. After the installer loads select Disk Utility from the Installer menu (or Utilities menu if using Tiger.) After DU loads select your OS X volume from the list on the left, click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the installer. Now shutdown the computer for a couple of minutes and then restart normally.
If DU reports errors it cannot fix, then you will need Disk Warrior (3.0.3 for Tiger) and/or TechTool Pro (4.0.5 for Tiger) to repair the drive. If you don't have either of them or if neither of them can fix the drive, then you will need to reformat the drive and reinstall OS X.
As relates to your first question regarding Software Update you may find a solution in the following:
When Software Update (SU) fails, it often gives the generic message: "Make sure you have permissions to write to /private/tmp/501/TemporaryItems/com.apple.SoftwareUpdate, then try again." However, there are many different reasons why SU can fail and not all reasons are related to permissions.
Here are some things to try to address the more common failure modes:
1) First, try to run it again. Sometimes if fails for no obvious reason but will then work normally. Perhaps this is related to funny business on the network connection.
2) Sometimes the problem really is due to permissions. Use Disk Utility to fix permissions on the hard drive.
3) Sometimes the /tmp logical link is broken for one reason or another. Here is a procedure to recover from this problem.
- Start the Terminal program from the Utilities menu
- Copy and paste the following two commands into the Terminal window. You will be asked for an admin password after the first command. Enter it (it is not echoed in any way) and press return. Note that the "l" character is an "el" and not "eye".
sudo mv /tmp /tmp_old
sudo ln -s /private/tmp /tmp
4) You can try to bypass SU completely and download via Apple's download website. If this procedure works, then it is very likely that SU did not work because the tar program is missing. You can test for this by starting the Terminal program again. Issue the command
tar
You have a tar program if you get a response such as "tar: You must specify one of the `-Acdtrux' options:"
You do not have the tar program if you get response such as "-bash: tar: command not found"
If you do not have the tar program, you will have to re-install it so that SU will work in the future. You can extract the tar program from your Panther Install CD with the aid of an application called Pacifist, available from
http://www.charlessoft.com/
5) A less common problem is that a program called pax is missing. To see if you have it, go to the Terminal program and type
ls /bin/pax (followed by a return)
If you get the response "/bin/pax", you have the program. If you do not have the program, you can install it from your Panther install CD with the aid of the Pacifist program.
6) Some problems are related to downloads which appear to be corrupted. These problems are not well understood, but one possibility is that corruption exists in the file system. To check this, boot off your Install CD and attempt to repair your hard drive with the Disk Utility program.
If none of these steps solves the problem, there is a way to get a more specific error message which might aid in debugging. Start the Console program from the Utilities menu. This will normally open the Console log on your screen. Then, attempt to do the Software Update. When it fails, it usually writes a few lines of output to t
