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We had to put our late 2011 macbook pro back to factory settings. My daughter is trying to download mavericks from the app store right now. She has been having trouble downloading imovie for. Download iMovie for macOS 10.15.6 or later and enjoy it on your Mac. With a streamlined design and intuitive editing features, iMovie lets you create Hollywood-style trailers and beautiful movies like never before. Download iMovie 9.0.9. What's New in Version 9.0.9. Addresses issues where iMovie does not recognize video cameras connected to your Mac.
As you have an old MacBook, you must know that iMovie comes preinstalled. Search on the Dock (the bar at the bottom of the display) the iMovie icon.
If you don't find it, you should have the DVDs that came with the MacBook. The Mac OS X Install Disc 2 includes the iLife apps (iPhoto, iMovie, iDVD, iWeb and GarageBand), so just insert it and install them. Then, open > Software Update and install the most recent version of them.
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If you haven't got these discs, call Apple to get replacement DVDs > http://support.apple.com/kb/HE57 Another option you have is to buy the latest iLife version (iLife '11) on Amazon, so you will get the most recent features