Can't install Digital Camera Raw Compatibility Update 2.2

Question

Software Update wants to install Digital Camera Raw Compatibility Update 2.2, but it always fails, saying: "The update “Digital Camera Raw Compatibility Update” can’t be saved. You do not have appropriate access privileges. The Installer package has been moved to the Trash. To try again, open the package from the Finder."
I've tried doing Repair Permissions in Disk Utility, but this has not helped. I'm using Mac OS X 10.5.5, all other recent updates have gone in fine.

Answer 1

I had the same problem. Deleting the contents of the HD/library/Updates worked.
Never the less I noticed that the permission set was different:
Original permission set: admin R&W, admin R only, everyone R only.
I also followed the Alias and found two files with the same permissions.
Re-downloading (via software update) revealed a new permission set:
(Me) R&W, Admin R&W, everyone Read only
In both the alias and the two files downloaded. Note that (Me) denotes your user with administrator access.
I believe that, since the update was downloaded automatically, the permissions were mismatched and instead of adding a system R&W privileges it added a second Admin Read only permission.
Adding an administrator user with read and write permissions should solve the problem (as long as you authenticate as that particular administrator when prompted for intall authorization).
Regards, Jaime.