This wikiHow teaches you how to open a DMG file on a Mac. Since DMG files are usually used to install applications on Mac computers, you cannot open them on Windows computers.
Step
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Step 1. Double-click the DMG file
After that, the Mac will try to open it and display a pop-up message "[File name] can't be opened because it was not downloaded from the App Store".
- If you do not see a pop-up window containing the message, continue to the "Review the DMG's contents" step at the end of this method.
- Since DMG files are generally downloaded, you can find them in the " Downloads " folder of the Finder window.
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Step 2. Click the OK button when prompted
After that, the pop-up window will close.
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Step 3. Open the “Apple” menu
Click the Apple logo in the upper-left corner of the screen. After that, a drop-down menu will be displayed.
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Step 4. Click System Preferences
It's at the top of the drop-down menu. After that, the “System Preferences” window will be opened.
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Step 5. Click Security & Privacy
It's at the top of the “System Preferences” window.
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Step 6. Click the padlock lock icon
It's in the lower-left corner of the window. After that, a pop-up window will be displayed.
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Step 7. Enter the password, then click the Unlock button
You can do this in the pop-up window that appears. After entering the password, you can edit the content or entries on this page.
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Step 8. Click Open Anyway
This option is to the right of the DMG file name that appears at the bottom of the page.
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Step 9. Click Open when prompted
After that, the DMG file will be opened so you can view its contents and continue with the installation process.
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Step 10. Review the contents of the DMG file
Usually, you use a DMG file to install the app. However, sometimes DMG files may contain photos or text files.
- Any file that ends in an.app extension is an installable application.
- It is possible that you may see the " Applications " icon in the DMG window. This is a shortcut to the “Applications” folder on your computer.
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Step 11. Install the DMG app
Locate the icon for the application you want to install (eg Firefox), then click and drag the icon onto the " Applications " icon in the window. After that, the application loaded in the DMG file will be installed. After the installation is complete, you can search for it in the “Launchpad” menu.