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Sometimes you may need to download the standalone installer file for a software update. These are available from the Apple Downloads Web page. The Software Update preference pane will force you to install software in the correct order, you should carefully read the stated system requirements before using a standalone installer. Be sure to install in the correct order and only on compatible systems when applicable. A standalone installer may be advantageous when you:
Anticipate needing the file again later.
Need to install on multiple computers and need a portable file.
Have a faster Internet connection available to you at another computer.
Have no Internet connection on the computer that needs the update.
