The following worked on my MacBook Pro Core 2 Duo running Mac OS X 10.6.2. Before I began, I noted where Disk Utility was in my Dock.
Before subjecting the Dock to unintentional poofing, make backups of the following files, by selecting them in the Finder and typing Command D:
1. ~/Library/Preferences/com.apple.dock.plist
2. ~/Library/Preferences/com.apple.dock.db
We now have two new files:
~/Library/Preferences/com.apple.dock copy.plist
~/Library/Preferences/com.apple.dock.db copy
Remove Disk Utility from the Dock. Poof!
Delete:
~/Library/Preferences/com.apple.dock.plist
~/Library/Preferences/com.apple.dock.db
Rename:
~/Library/Preferences/com.apple.dock copy.plist to ~/Library/Preferences/com.apple.dock.plist
~/Library/Preferences/com.apple.dock.db copy to ~/Library/Preferences/com.apple.dock.db
Launch Activity Monitor, located in /Applications/Utilities. Force the process named Dock to quit. When the Dock relaunches automatically after a few seconds of sheer Docklessness, note that Disk Utility is right where it belongs in the Dock.
