Dmg Files Won't Open

Posted By admin On 24/09/19

Scroll down to “Update and Solution” to see how to get this to work.

Ways of Opening a DMG File in Windows: DMG Extractor (Free and Paid): The best and the most professional tool for opening a DMG file in Windows is DMG Extractor.It can open a variety of Disk Image Files and it also demolishes the need to convert the DMG file to ISO for use in Windows. Jul 20, 2017  Still, you probably won’t install all of your software this way. Most macOS applications downloaded from outside the store come inside a DMG file. Double-click the DMG file to open it, and you’ll see a Finder window. Often these will include the application itself, some form of arrow, and a shortcut to the Applications folder. Is it just that.dmg that won’t open? Have you tried a different one to compare? Basically there’s no reason that should be happening. So unless it’s happening with. DMG files are mostly supported on Mac operating system. But many of you like me love to use virtual machine and try to convert Mac OSX DMG files to ISO so that you can use it on Windows platform. As Windows operating system doesn't supports DMG file. In order to make it supportable you have to covert these DMG files into ISO format.

Apple recently released new installers for Mac OS X/OS X/mac OS to deal with expired certificates:

Three of the six are links to the Mac App Store:

The other three are URLs to download DMGs:

  • macOS Sierra – InstallOS.dmg
  • OS X El Capitan – InstallMacOSX.dmg
  • OS X Yosemite – InstallMacOSX.dmg

Today I tried (and failed) to create a new Virtual Machine in either Parallels or VMware Fusion using one of these DMGs, specifically, the El Capitan one.

So if original disk has multiple tracks it won't be properly stored in ISO formats and workarounds like CUE/BIN, CCD/IMG and MDS/MDF formats will be needed to store information properly. ISO is a popular method to distribute operating systems to developers and end users. For example Microsoft uses ISO files to distribute its Windows 10 OS to users. Open DMG File. The usage of the DMG file extension is in the context of a mountable disk image file which is generated by the Mac OS X Operating System platform. Once the file is opened, the system will mount it in a virtual disk located on the user's desktop. You can't extract more than 5 files from a DMG simultaneously, and it simply won't work with encrypted files or those bigger than 4 gigabytes. Neither 7-Zip nor DMG Extractor are the ultimate solution, though. There are some DMG files that 7-Zip, nor other alternatives that we've tried will open.

I will explain what I did, and where I got stuck, in the hopes that someone else might figure out what I did wrong and point me in the right direction.

Download the DMG

Apple has created three DMGs for Yosemite, El Capitan, and Sierra, but couldn’t be bothered to give them useful names, so Yosemite and El Capitan are called ‘InstallMacOSX.dmg’ and Sierra is ‘InstallOS.dmg’.

Likewise the DMGs aren’t named usefully when you mount them either, so make sure you name the DMGs well when you download them to avoid confusion. Here’s how to download it and rename it at the same time

Mount the DMG

Open the ‘~/Downloads/InstallElCapitan.dmg’

That will leave you with

“/Volumes/Install OS X/InstallMacOSX.pkg”

Extract the App

Don’t try to install from that .pkg file, it probably won’t work unless the Mac you’re using is capable of running El Capitan:

Instead, open it with Suspicious Package which will let you examine the contents of the .pkg file, as shown here:

Note the area in the red box. Obviously that’s not the full installer, despite the .dmg being over 6 GB. But let’s export it anyway:

Save it to /Applications/ (or wherever you prefer, but that’s where I’ll assume it is for the rest of these instructions).

Dmg File Won T Open On Mac

Don’t eject “/Volumes/Install OS X/InstallMacOSX.pkg” yet, we still need to get the actual .dmg from it.

Get the other DMG

Download The Archive Browser if you don’t already have it (it’s free!) and use it to open “/Volumes/Install OS X/InstallMacOSX.pkg”.

It will look like this:

Click on the triangle to the left of “InstallMaxOSX.pkg” to reveal its contents, and select the “InstallESD.dmg” file from it.

Once it is selected, choose “Extract Selected” from the bottom-left. Save it to ~/Downloads/ (it won’t be staying there long).

Ok, this part could be confusing…

When The Archive Browser exports the file, it will not just export the “InstallESD.dmg” file. First it creates a folder “InstallMacOSX” and then it created “InstallMacOSX.pkg” inside that folder, and the “InstallESD.dmg” file is put inside the .pkg… but you can’t see it, because the .pkg file won’t let you open it.

That’s OK, because we’re going to use Terminal.app to move the file into place anyway.

First we need to create a directory inside the ‘Install OS X El Capitan.app’ which we previously saved to /Applications/. We’re going to use the same folder for two commands and we want to make sure we get it exactly right both times, so we’ll make it a variable:

Then use the variable with mkdir to create the folder:

and then we need to move the “InstallESD.dmg” file into that folder

Note: you probably want to trash the ‘~/Downloads/InstallMacOSX/InstallMacOSX.pkg’ (and its parent folder) now that it is empty, to avoid confusion later

Now if you look at the ‘Install OS X El Capitan.app’ in the Finder, it should show itself as 6.21 GB:

So close, and yet…

VMWare was willing to start trying to make a virtual machine using the app, but it failed when it came to the actual installation part:

I don’t know what to try next. Parallels would not use either the ‘Install OS X El Capitan.app’ or the ‘InstallESD.dmg’ to try to create a new virtual machine.

Update and Solution

Dmg Files Won't Open Mac Sierra

I posted a question on the VMware Fusion support forum asking how to do this, and someone came up with a very clever solution, which I will replicate here in case others are interested. The idea is simple, but I never would have thought of it.

  1. Create a virtual machine of any version of macOS, even the current version that you are using on your Mac.

  2. Inside the VM, download the .dmg (see below) and mount it.

  3. Launch the .pkg inside the .dmg.

  4. The .pkg seems to understand that it is inside a VM, and will install the app, which it would not do outside of the VM. Note that the Installer.app says that it will only take a few megabytes, but that is incorrect.

  5. Find the “Install OS X El Capitan.app” (or whatever the app name is) in the /Applications/ folder inside the VM. It should be over 6 GB in size.

  6. Copy the “Install….app” from the VM out to your actual Mac.

    This version of Mac comes with an interesting feature called time machine. Yosemite 10.10.5 dmg. It allows the user to back up the deleted or replaced by another version of the file.

  7. Create a new VM using the “Install….app” from the /Applications/ folder on your Mac.

Step #4 is the part that I never would have guessed. The .pkg would not install the app outside of a VM, but will install it inside of a VM.

This worked perfectly with the El Capitan .dmg file, and I’m currently doing the same with Yosemite and Sierra. Then I’ll try the older versions of Mac OS X from old installers that I have from before they disappeared from Apple’s servers.

Update 2

Turns out that Rich Trouton wrote about this technique back in early 2017:

But I wasn’t working with VMs at the time, so I must not not stored that in my long-term memory.

Update 3

I had saved the older installers for Lion, Mountain Lion, and Mavericks, which are no longer available for download.

Each of them still installed as a VM. Apparently they were not signed with the certificates that expired.

Older versions of Mac OS X (10.6.8 and before) are not available to virtualize.

This brief guide will take you each step of the way through opening and accessing the contents of .rar files using Windows 10.

How To Extract Dmg File

NOTE: the steps in this tutorial are idential if you’re trying to open a .DMG or .RPM file in Windows 10 as well – so this guide could just as easily be called “How to Open RAR, DMG and RPM Files in Windows 10” :) Those formats are typically found on Mac and Linux/Unix systems – so being able to open them on a Windows 10 laptop/desktop/tablet can be very handy.

My .dmg File Won't Open

  1. Going into almost no detail at all, a .rar file is a lot like a .zip file. It’s one or more files/folders all combined into one file – a RAR. Here’s how you open those files so you can get to the contents inside.
  2. Unlike ZIP files, RAR files require software that doesn’t come included with Windows itself. Fortunately there’s a fantastic, small and free app that does let you open .RAR files. Head over to the 7-Zip download page (link opens in a new window/tab) and download the 7-Zip for 64-bit Windows x64 (Intel 64 or AMD64) version of 7-Zip, unless you’re absolutely certain you don’t have a 64-bit version of Windows 10.
    3. Double-click the 7-Zip installer file to install the app. Make sure to install it to the default location – which is in C:Program Files. If you need to install it to another location you can, just make sure to remember exactly where, you’ll need to know in an upcoming step.
  3. After you’ve installed 7-Zip, double-click (or tap if you have a Windows 10 tablet) the .RAR file you want to open.
  4. Select More apps from the menu that appears.
  5. Now select Look for another app on this PC
  6. When the “Open With” dialog box appears, double-click your C: drive and then the Program Files folder (as illustrated in the screenshot below).
  7. Open the Z-Zip folder.
  8. Select the file 7zFM.exe and then click Open
  9. 7-Zip will launch and open the .RAR file. Now it’s time to extract (copy) the files and folders out from inside the RAR. Select all of the files/folders and then click the Extract button.
  10. By default, the files and folders will be extracted to the same location the RAR file is in – click OK to begin that process.
  11. Depending on the size and the number of files stored in the .RAR file, it may take anywhere from under a second to a few minutes to copy all of that data. Once the process has completed, all of data that was inside the RAR file is now accessible! Note: the next time you have to open a RAR file you won’t have to repeat this process – the RAR will simply open with 7-Zip.
  12. That’s it – you’re done!