Just like ISO files, the DMG file format is often used to save compressed app installers instead of using physical disks.

A DMG file works the same way as ISO files. If you’ve worked with Windows before, then you have a pretty good understanding of what an ISO file is. It is the macOS version of Windows’ ISO files. A DMG file, also known as Apple Disk Image or macOS Disk Image file, is a digital reconstruction of your physical hard drive. DMG is a file format that you usually encounter when using a Mac.

What is a DMG File?īefore discussing the error, let us first understand what a DMG file is and what it is used for.

If you are getting this error when opening your DMG files, this guide will be quite helpful for you to resolve this error and successfully run your problematic DMG files. About Outbyte, uninstall instructions, EULA, Privacy Policy. What’s even more frustrating is when the DMG files you want to mount are your backup files from your previous macOS installation and they contain important data and files.Ĭompatible with: Windows 10/11, Windows 7, Windows 8 This error can be quite irritating if you want to install a specific app on your Mac and the downloaded installer from the internet is not recognized by macOS. There are also instances when macOS says that the DMG file can’t be mounted because it is still being downloaded, but the file has been downloaded completely on the device. The files seemed to be downloaded successfully, but when they try to mount the DMG file, they get a notification that the disk image can’t be opened because macOS can’t recognize the file. Other Mac users encountered the error when downloading files from the internet, such as app installers or software updates. Unfortunately, once his Mac was back up and running again, the DMG files he created were not recognized by the freshly installed operating system. The user had to do a clean install of the entire operating system, so he saved the important data in a DMG format. For example, one user posted on Apple’s support website about his Mac not being able to recognize the DMG files he created as a backup. Some app installers also come in DMG format and the Mac user just needs to mount the file to extract the installer and run the package.īut for some reason, several Mac users have been experiencing issues with DMG files. exe files to execute programs while macOS uses a. One of the major differences between Windows and macOS is the way they read, write, and install files and applications.

Mac disk image not recognized