How to make external disks reappear on desktop in Mountain Lion? After upgrading from Lion to Mountain Lion, my MBP does not show icons for external drives on the desktop any more. In the Finder preferences, “External disks” is checked under “Show these items on the desktop”. Any ideas?
Somehow, the upgrade to Mountain Lion enabled the hidden Finder setting that completely hides desktop icons. You can reenable it using

defaults write com.apple.finder CreateDesktop -bool true