In the Energy Saver preference pane of System Configuration in OS X 10.8.2, any changes made are lost upon restart.
Here is an abridged list of things I tried that did not solve the problem:
- Disk Utility repair permissions function
- Various command line repair permissions functions on ~/Library and sub folders
- Deleting com.apple.systempreferences.plist and many other .plist files
- Setting and reconfiguring with pmset on the command line
- Performing an SMC reset
- Performing a PRAM reset
I searched through a bunch of forum posts, Apple articles and blog posts to no avail.
What I found was that this file
was being modified whenever I changed the values in Energy Saver Preferences, and for some reason it was getting overwritten or reset whenever I rebooted.
To prevent this, I locked (made immutable) the file with this command:
sudo chflags uchg /Library/Preferences/SystemConfiguration/com.apple.PowerManagement.plist
And now the Energy Saver Preferences survive a reboot. If I need to change them again, I’ll have to manually unlock the file, make the changes, and then lock it again, so this is just a workaround until I find out what is causing the problem in the first place. If you have any ideas, let me know.