Macintosh OS/dmg files


I  purchased a magazine online, and the publisher provides a
free digital copy  to all customers.
The digital file is a download file The format is .dmg
The site states clearly, for Mac users click the dmg version.

My mac mini states FILE TYPE NOT RECOGNIZED.
I have downloaded other files from the webm compile3d as dmg.
A major publisher couldn't be providing download files that
are incompatible with a mac ?

What's the mystery with this file format ? DMG.  HUH ?

DMG files are "Disk Image" files.  They are treated as if they are disks (floppy or hard drive or flash drive)
It is a common format, and is used for many purposes - installers most frequently.

Downloading files over the internet can break the files, errors are created.  The first suggestion is to re-download the problem file.
Disk Utility is the OSX utility that allows you to create, mount, and troubleshoot DMG files. It is in the Utilties folder in the Applications folder.

IF other DMGs work for you, and not the ones provided by a single source, I would contact that source, or search for [source DMG files download Mac problem "FILE TYPE NOT RECOGNIZED"]
Take the DMG to another Mac and test.

If your computer opens some and not others (including these), your version of Disk Utility may be old (as well as your OSX version)

ONE of many links from a Google "dmg file type not recognized mac os x"

Macintosh OS

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David Anders


Seattle - The Computer Guy - 15 yr veteran Mac/PC/network problem solving. Clients are design firms, artists, freelancers and photographers. PLEASE PLEASE provide EXACT info for Mac Model and OS Version. RAM installed - added cards - external devices - recent changes. Do you do MONTHLY MAINTENANCE? With what Utility? What you have tried and what result do you want.


First computer experience 1969. Worked in 3 computer stores. Setup First Mac and First IBM-PC.

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