Basics: Installing DMG Files
Posted October 1st, 2006 - 11:09 PM by Cujo || Organized in BasicsOne of the first things I did on my new Mac was go online and download Firefox as it is my browser of choice. The download process was the usual download to your computer but the file had a DMG extension, something I wasn’t familiar with. Being from the Windows world I equated this with an EXE extension and clicked the file assuming the installation would begin. I assumed it was a general installation as an EULA appeared and I accepted then saw the following screen:
I clicked on the Firefox logo assuming this would launch the program and that this window was just showing me Firefox in a folder. I proceeded to use the program believing it was installed and removed the DMG file that was downloaded as I thought it was no longer needed (such as Windows install files). However the next time I went to use Firefox it wouldn’t load, the problem was I didn’t install it.
The DMG file actually “mounts” an image of the program onto your Desktop which looks like this:
If you click on this image it will open the same window as you saw above. What that window is showing you is to move the Firefox icon on the left into your Applications folder — you accomplish this by simply dragging the icon into your folder. You will then see the program start installing. After the installation is complete you are free to move both the DMG file and the Firefox drive image icon into the trash. When you drag the drive image to the trash the trash icon will switch to an eject button and this will be discussed in a later post.
Most programs downloaded from the Internet will have this DMG extension and will feature an install window which varies by program. Some are more intuitive on what you should do and some are a little more abstract such as the Firefox one. For example, below is the install window for Adobe Lightroom Beta 4.
As you can see, this install shows the movement of Lightroom into the Applications folder with a bolder arrow. However if you didn’t know that you actually had to drag the icon into the folder you still might make the same mistake I did when I first tried installing my first downloads on the new Mac.
Installation of programs is as simple as dragging the icon into the Applications folder, no further steps are needed. It really is that easy.
October 2nd, 2006 at 11:04 pm
[...] A definite must have application for any owner of a Mac is AppZapper. In my previous post Installing DMG Files I mentioned that installing applications on the Mac is as simple as dragging the application into the Application folder, unfortunately uninstalling an application isn’t as easy. Enter AppZapper: [...]
October 3rd, 2006 at 10:35 am
Taking screenshots on the pc ?
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October 3rd, 2006 at 11:09 am
I’m not sure if you’re asking if I took the screen shots on a PC or if you want to know how to take a screen shot on a PC.
For the first one, the screen shots were done on a Mac (a post coming soon).
For a PC there’s a Print Screen button found near the top of your keyboard, hit Alt+Print Screen and this will capture your current winidow, just hitting Print Screen will captrue the entire screen. This will then put the screen shot onto your clipboard, from there find either an image application or any other type of application and paste the screen shot into it (Edit > Paste or Ctrl+V).
Who would have thought I’d be giving PC help on I’m A Mac?
March 22nd, 2007 at 10:03 pm
MAN!!! I couldn’t figure out what the hell to do with the stupid firefox ,dmg file. I would delete it, and couldnt find the program any more! I’m a windows power user, so OS X has thrown me a few curveballs, but nothing as frustrating as this one. THANK YOU!
April 6th, 2007 at 9:00 pm
What if it won’t let me drag and drop firefox into the applications folder?
April 13th, 2007 at 8:51 pm
Good lord, thank you so much. It has been about 15 years since I owned a Mac, and I don’t remember anything at all. I did the exact same thing initially: double-clicking and assuming it was installed. Thanks to your guide showing up on Google, I know how to install sleek new programs now!
May 21st, 2007 at 6:50 pm
Ahhh, so thats how it works. They really should have a call out when the pointer hovers over the icon. I had the same problem last night. Then I found I could right click and copy contents, then paste contents. It seemed to work but OO only opens writer. Looks like I’ll try again tonight! Thanks.
June 13th, 2007 at 11:34 pm
Thanks for the explanation. That was a *big* help.
October 29th, 2007 at 9:39 pm
When I drag the dmg file acquired at the website into the Applications folder it simply moves there. It does not install it. When I double click on the dmg file the program opens but in a separate finder window in top left section (with hard drives and network) with an eject icon next to the title.
January 4th, 2008 at 6:07 am
Thank for the explanation. I’m a newbie in mac. thanks again.
January 16th, 2008 at 6:37 pm
Thank you, thank you, thank you. I am a power user in the PC world. My son wanted a Mac and he got one. Every time the darn thing goes down, I have to fight with the “closed system” attitude of Apple. The latest was a Safari crash. Reinstalled the OS, the program, even upgraded both. Nothing. In the PC world when it is not going well you find open source software that you know will work. Found Firefox for the Mag. The .dmg extension did me in however. That was until I found your site (Google search). Done. Thanks again