For most users, the direct way to install iMovie is via the official store: Open the on your Mac. Search for "iMovie" . Click Get or the Cloud icon to download and install. iMovie will appear in your Launchpad once finished. Installing on Older/Unsupported macOS
If you intentionally chose version 10.2.5 to preserve system compatibility, open the Mac App Store , go to Settings , and uncheck Automatic Updates . This prevents macOS from overwriting your custom installation with a newer, potentially unsupported version of iMovie. imovie 1025 dmg install
A window will pop up saying "Opening 'iMovie_10.2.5.dmg'..." followed by "Verifying...". Let this process finish. For most users, the direct way to install
For security, only use DMGs from known locations to avoid malware. 2. Installation Steps For most users