The OS X Mountain Lion v10.8.1 Update is recommended for all Mountain Lion users and includes general operating system fixes that improve the stability, compatibility, and security of your Mac.

Updating your system

You should back up your system before installation; you can use Time Machine.

Do not interrupt the installation process once you have started to update your system.

You may experience unexpected results if you have third-party system software modifications installed, or if you've modified the operating system through other means.

Choose Apple () menu > Software Update… to check for the latest Apple software via the Mac App Store, including this update.

Other software updates available for your computer may appear, which you should install. Note that an update's size may vary from computer-to-computer when installed using Software Update. Also, some updates must be installed prior to others.

You can also download the manual update installer. This is a useful option when you need to update multiple computers but only want to download the update once. These versions of the standalone installers are available from Apple Support Downloads.

Additional Information

What is included?

This update includes general operating system fixes that improve the stability and compatibility of your Mac, including fixes that:

• Resolve an issue that may cause Migration Assistant to unexpectedly quit
• Improve compatibility when connecting to a Microsoft Exchange server in Mail
• Address an issue playing audio through a Thunderbolt display
• Resolve an issue that could prevent iMessages from being sent
• Address an issue that could cause the system to become unresponsive when using Pinyin input
• Resolve an issue when connecting to SMB servers with long names
• Address a issue that may prevent Safari from launching when using a Proxy Automatic Configuration (PAC) file
• Improve 802.1X authentication with Active Directory credentials

Important: Information about products not manufactured by Apple is provided for information purposes only and does not constitute Apple’s recommendation or endorsement. Please contact the vendor for additional information.