This article shows you how to open a DMG file on Mac. Archives of this type are mainly used for installing applications on OS X and macOS systems, so they are almost useless on Windows systems.
Steps
Step 1. Select the DMG file under examination with a double click of the mouse
This will cause the Mac to attempt to open it automatically showing you a pop-up window with the following message: "Cannot open [Filename] because it was not downloaded from the Mac App Store".
- If this dialog box does not appear, jump directly to step number 10 of the article.
- Since DMG files are downloaded in most cases, they are normally stored automatically in Finder's "Download" folder.
Step 2. Press the OK button when prompted
In this way the appeared window will be closed.
Step 3. Enter the "Apple" menu by clicking the icon
It features the Apple logo and is located in the upper left corner of the screen. The appropriate drop-down menu will appear.
Step 4. Choose the System Preferences item
It is located at the top of the "Apple" menu. This will bring up the "System Preferences" window.
Step 5. Click the Security and Privacy icon
It is located at the top of the "System Preferences" window.
Step 6. Click the lock icon
It is located in the lower left part of the newly appeared window. When finished, a small pop-up window will appear.
Step 7. Type your Mac login password and press the Unlock button
Enter the security password of your account in the small pop-up window that appears to have the possibility to change the configuration settings in the "Security and privacy" section.
Step 8. Hit the Open button anyway
It is positioned on the right of the name of the DMG file in question at the bottom of the window.
Step 9. Press the Open button when prompted
This will open the selected DMG file allowing you to view its contents and continue with the installation.
Step 10. Review the contents of the DMG archive
In most cases DMG files are used for installing programs and applications. However, at times, they may contain images or text files.
- Any file with the.app extension identifies a program that can be installed inside the Mac.
- Most likely within the window showing the contents of the DMG file you will also see an "Applications" icon. This is the link to the Mac's "Applications" folder.
Step 11. Install the app or program contained in the DMG file
Locate the icon of the application you are trying to install (for example Firefox), then select and drag it to the icon of the shortcut to the "Applications" folder inside the window. In this way the chosen file will be installed on the Mac. At the end of the process you will find the relative icon in the Launchpad menu.
