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dmg downloads won't mount

Trying to update some software and I'm finding that dmg files won't mount.

The dmg files work on another computer running the same version of OSX.

I don't get the standard warning telling me that I may be downloading an application.

Disk utility won't verify it because it won't mount.

I did run permissions and rebuild Launch services database with ONYX but the problem persists.

I can network the other computer and manage the dmg and update from there but I need to fix this.

Any advice?

Dual 2GHz G-5, Mac OS X (10.4.11)

Posted on Feb 3, 2008 11:21 PM

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Question marked as Top-ranking reply

Posted on Feb 4, 2008 12:00 AM

Just for curiosity, if you do a Finder's *Get Info* on any of the errant .dmg files, what application gets listed as the default to open them with?

It should normally be DiskImageMounter. If it isn't, open the drop-down menu and if needed select Other... and look for this app inside /System/Library/CoreServices/. If the correct mapping wasn't there, you can try and click on *Change All...* to force setting it.
6 replies
Question marked as Top-ranking reply

Feb 4, 2008 12:00 AM in response to Sweejak

Just for curiosity, if you do a Finder's *Get Info* on any of the errant .dmg files, what application gets listed as the default to open them with?

It should normally be DiskImageMounter. If it isn't, open the drop-down menu and if needed select Other... and look for this app inside /System/Library/CoreServices/. If the correct mapping wasn't there, you can try and click on *Change All...* to force setting it.

Feb 4, 2008 12:19 AM in response to Sweejak

I had that happen on one of my Macs after an OS X update that didn't complete fully. What might get your DMGs to mount again (until you reboot) is:

1. Go into terminal (in /Applications/Utilities)

2. type

su [username that has admin rights]

you will be asked for your admin password.

3. Then run these two commands in turn, which restart the part of OS X that deals with DMGs

sudo kextunload -c com.apple.AppleDiskImageController

sudo kextload -b com.apple.AppleDiskImageController

4. Now try to mount a .dmg that you know is a good one.

If that works, I think you should re-install the latest combo updater for your version of OS X, to hopefully put things right properly. You don't want to be doing those steps above after every reboot and the DMG mounting not working points to something being broken that hopefully re-applying the latest combo updater will put right.

Feb 19, 2008 5:00 AM in response to Ted Harper

cheers Ted but this doesn't work for me - see my terminal window contents

Last login: Tue Feb 19 12:43:35 on console
Welcome to Darwin!
andrew-beardsmores-powerbook-g4-17:~ andrewbeardsmore$ sudo kextunload -c com.apple.AppleDiskImageController
Password:
kextunload: terminate instances for class com.apple.AppleDiskImageController succeeded
andrew-beardsmores-powerbook-g4-17:~ andrewbeardsmore$ sudo kextload -b com.apple.AppleDiskImageController
Can't find superclass for 15KDIBackingStore : 9KDIObject
kextload: a link/load error occured for kernel extension /System/Library/Extensions/IOHDIXController.kext
load failed for extension /System/Library/Extensions/IOHDIXController.kext
(run kextload with -t for diagnostic output)
andrew-beardsmores-powerbook-g4-17:~ andrewbeardsmore$

Any ideas anyone ?

Looks like an archive and reinstall to get a chance at reapplying the combo updater ?

Thanks

Andy

dmg downloads won't mount

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