OSX Tips

Mountain  Lion  Changes

                 Previous                        Home                         Contact                           Next


                                                    Home                                  Contact                                 

A number of appearance and functional things in Mountain Lion are different from Lion. 

       (If you skipped Lion, see Some Changes in Lion.)

A few that may be especially disconcerting or confusing to those accustomed to earlier versions of OSX, that aren't mentioned or aren't clear in Apple's What's New document:


  1. If your Mac crashes, upon restart there's a prompt allowing to not reopen Apps.

  2. The .lockfiles in /Library/Preferences and ~/Library/Preferences are gone.

  3. If you upgrade or transfer from Lion, they’ll remain, unused.  Delete if you wish.

  4. Setup Assistant and Migration Assistant:

  5. You cannot transfer from Macs running Tiger or earlier to Mountain Lion.

  6. To transfer via Firewire or Thunderbolt, select From Time Machine or other disk, not From another Mac.  See Using Setup Assistant on Lion and/or Using Migration Assistant on Lion.

  7. Safari’s Empty Cache option has been removed as a separate item.

  8. Safari > Reset >Clear History also clears the caches, website icons, and recent searches.

  9. To only clear the caches, enable the Develop menu (Safari > Preferences > Advanced) and use Develop > Empty Caches.

  10. The kernel.log is gone.

  11. Kernel messages are now in the system.log.


  1. Save a Version is now just Save.

  2. Save As is back.   Hold the Alt/Option key while clicking the File menu item.

    Or use the Shift+Alt/Option+Cmd+S shortcut

  1. Automatic file locking is gone.

  2. You can still lock or unlock files by clicking the name in the title bar.

  3. AutoSave can be partially turned-off.

  4. Via System Preferences > General > Close windows when quitting an application.

  5. If you select Save when closing or quitting, that will make a new Version.


  1. You can now specify multiple backup destinations.

  2. See Rotating Time Machine Backup Disks for details and instructions.

  3. Time Machine backups to a network drive can be encrypted.

  4. See How do I set up and use encrypted backups?

  5. The Browse Other Backup Disks option DOES NOT WORK on 10.8 or 10.8.1

  6. But has been fixed, effective with 10.8.2.

  7. The TM menubar icon only spins during actual copying

  8. Especially if there’s a long preparing and/or finishing-up phase, performance may suffer with no indication a backup is running.

  9. The first backup after upgrading may send many thousands of messages to the system.log: "Error (256): fetching properties: Error Domain=NSCocoaErrorDomain Code=256 "The file . . . couldn’t be opened. . ."  These don’t appear to indicate an actual problem.


  1. The iCal app is now named CALENDAR

  2. CALENDAR alerts won’t run Applescripts

    See https://discussions.apple.com/docs/DOC-4082 for an alternative.

  1. The AddressBook app is now named CONTACTS


  1. Sidebar sections (Favorites, Shared, Devices) can be re-organized

  2. An internal or external disk can be encrypted by control-clicking (right-clicking) it in the Sidebar or desktop icon

  3. Sidebar icons still have no color, and apps in the sidebar have only generic icons

  4. 3rd-party Lion apps to add them, such as ColorfulSidebar and LionTweaks DO NOT WORK on Mountain Lion.

  5. The SideEffects app does seem to work for most folks on Mountain Lion, but not all.