# New to Macs - What is a .Dmg file?



## mykelee (Nov 23, 2003)

Please excuse the question but I am normally a PC user and purchased myself a new iMac with OS X

I've been trying to download some file from the web which is a DMG file. But after the download when I click on it I get some "can't mount" error.

1) What is a DMG file. Is it that the file is damaged or it needs something else with it.
2) What is the equivalent of a PC .ZIP or .EXE file for Macs then?


Many THanks

Michael


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## dave17lax (Nov 23, 2003)

A dmg is a disk image. I think of them as a disk within a disk... If it won't mount it's possible the file is corrupted, or incomplete. Also I think there is a way to not automatically verify dmg files, which will sometimes let you mount dmg's with "weird behaviors". I could be wrong about that one though.

Macs "don't do" executable files. One reason it's harder to make viruses for mac os . 

As of 10.3, the OS can zip and unzip zip files, but the standard archive that you may see for the mac is .sit, which is a stuffit archive.
There's also gzip and tar, but I don't really know much 'bout those.


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## adambyte (Nov 23, 2003)

.sit and .zip files are compressed archives which can be expanded.

Product Installed.pkg (package) is kinda like the equivalent of a "setup.exe" ... it's a program that's an installer.

.img or .dmg is a virtual "disk image." Double click it, and you should get a virtual disk on your desktop. Copy the program from the virtual disk to your hard disk applications folder, and you're set. You can then "eject" the virtual disk.

Agreed... sounds like your .dmg didn't download correctly. Corrupted, most likely.

Welcome to the Mac.


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## bobw (Nov 24, 2003)

What is the name of the file you're having a problem with, and the URL for it?


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## mykelee (Nov 25, 2003)

Deal All

Thanks for the info! Still very excited to get my Mac going to its full potential.

As for Bobw's question, I dont have the link as I cant find it now. I was trying to download the copy of some non region DVD player for my Mac (I think its called VPC). I tried downloading this several times and aint had no luck

THanks
Myke


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## Excalibur (Nov 25, 2003)

VLC? www.videolan.org?


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## Durandle (Nov 25, 2003)

Just a quick warning - make sure you are not using "Internet Explorer" as it really is not very good on the Mac side (as it is no longer being updated) - it tends to currupt downloads and sometimes chops the end of the file off (hence a DMG file would not work).


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## Satcomer (Nov 25, 2003)

mykelee said:
			
		

> Deal All
> 
> Thanks for the info! Still very excited to get my Mac going to its full potential.
> 
> ...




I'm not sure if you ever seen VersionTracker.com. The page for the VLC download (with alternate download sites) is here. 

Plus, OS X is based on BSD which is a form of Unix. So I little preventive maintenance can go a long way! IMHO after most every major software install (even from Apple) a person should go to Applications->Utilities->Disk Utility and run Repair Permissions. Unix uses all kinds of Permissions for files and a lot of software developers still haven't figured then all out yet. So running Disk Utility and Repairing Permissions will save many future software headaches. 

One more thing, you can always do a Get Info on a file by highlighting a file and select File->Get Info or do a command[the Apple button]+i (the same output). Then a small window opens. Inside that window is an 'Open With' and you can choose which program open the file. The one mine is set at is DiskImageMounter and .dmg files all open good. Maybe you should check to see what the file is set to open with. That would be a good start.


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## mykelee (Nov 25, 2003)

This is where I am trying to download the non region DVD player and I cannot get the Mount file to work. 

http://www.videolan.org/vlc/download-macosx.html

I double click the DMG file downloaded and I get a "The following disk image failed to mount"
VLC-0.6.2.dmg Error -36870208

I also used IE to do this download

Any ideas?
Michael


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## bobw (Nov 25, 2003)

Try using Safari or another browser. I just downloaded with Safari and it opens fine.


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## mykelee (Nov 27, 2003)

I have tried using both Safari and Explorer.

I tried downloading MSN Messenger and also the VLC program for the non region DVD player but I have no luck. I keep getting the Cannot Mount error.

Is there something wrong that I am doing on my Mac?


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## Decado (Nov 27, 2003)

it doesnt sound like you are doing anything wrong. in fact, the .dmg-file should automount and place itself as a harddrive on you desktop.

Are you using Jaguar (10.2) or Panther (10.3)?
In panther when you select the .mg-file and choose "show info" and then "open with" it should say that it will open with something called "DiskImageMounter".


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## ex2bot (Nov 28, 2003)

I wonder if you're having problems because of a bug / messed up os install issue I just read about in one of the other threads.

Look for the thread called "Images Fail to Mount on 20" iMac" in this forum (System and Software).

Or click here ---> http://discussions.info.apple.com/WebX?128@176.Mc2IafvUluE.24@.599c3f63

Doug


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## mykelee (Nov 29, 2003)

Doug 
Their problem sounded very similar. However I have no clue what to do next.
Are they suggesting that a reinstall of 10.3.1 will work.
In simple terms as I am not familiar with Apples (more technical on PCs), how do I do this if my system I just bought already came with 10.3.1

Many Thanks

Michael


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## Decado (Nov 29, 2003)

Go here and download x.3.1:
http://www.apple.com/downloads/macosx/apple/macosxupdate_10_3_1.html

then use the application called "Disk Utility" that you find in Applications / utilities, to burn a cd from that disk-image. then install from the cd.

several of them wrote that it worked, but for some it didnt.
dont forget to delete the receipt called "MacOSXUpdate10.3.1.pkg" from macintosh HD/library/receipts before doing the reinstall. 

good luck!
(and if it doesnt work, soon 10.3.2 will be out for download)


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## mykelee (Nov 29, 2003)

Yes! The reinstall of 10.3.1 worked. I can now see the DMG files and install them. Also my Nikon camera is immediately recognised thru the USB

Thanks all

Michael


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## ex2bot (Nov 29, 2003)

Glad you solved your problem, mykelee.

Doug


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## gemini_boy (Dec 3, 2003)

I hate to say this but I am having a similiar problem. I have been a mac user for about 3 days now (hehe) and I recently downloaded iBlog from the .mac site. This file and numerous others of the .dmg file type fail to mount 

There is a pause and then i get this message:
The following disk images failed to mount
iBlog1.3.4.dmg error -536870208

I have downloaded this file about ten times and numerous other dmgs, all give me the same error.

TIA


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## Decado (Dec 3, 2003)

Then do what the Mykelee did 
(download macos x.3.1 updater, make a cd of it using Disk Utility (located in applications / utilities) trash the MacOSXUpdate10.3.1.pkg (located in harddrive/library/receipts) and then install the update from the cd you burned.
Hope it helps.


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