Prevent Mac From Mount Dmg On Startup

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  1. Prevent Mac From Mount Dmg On Startup Windows 7
  2. Mac Os X Dmg File
  3. Prevent Mac From Mount Dmg On Startup Windows 10
How to mount dmg file

Sometimes, it can be useful to prevent a given volume from mounting at boot. You might want to hide an old OS version from Spotlight corruption. You just might not want to clutter your desktop.

Download mac os iso image.

Note: Encrypted disks are unlocked before the fstab file is read. In order for this procedure to work with an encrypted disk, you must first mount the disk, unlock it, and save the password in your keychain.


Sep 10, 2018 This wikiHow teaches you how to prevent a startup application from running on your Mac. Open the Apple Menu. Click the black Apple icon in the upper-left corner of the screen. Click on System Preferences. Click on Users & Groups. It's near the bottom of the dialog box. Click on the Login Items tab. May 13, 2013 You can mount and unmount drives, volumes, and disks from the command line of MacOS and Mac OS X. For many users, the easiest way to unmount a drive in Mac is to either just drag a volume into the Trash, use the eject keys, disconnect the drive, or use one of the force eject methods. Sep 26, 2018  Reboot (or start up) the Mac and immediately hold down the OPTION key on the keyboard At the boot selector screen, choose “Install macOS Mojave” from the startup options Once you boot from the macOS Mojave installer drive you will see the familiar macOS Utilities screen from which you can start the macOS Mojave install or update process.

Prevent Mac From Mount Dmg On Startup Windows 7

Jan 26, 2019  Forgot your Mac password? 3 ways to unlock startup disks encrypted with Apple's FileVault by Jesus Vigo in Security on April 19, 2018, 11:36 AM PST. Nov 24, 2016  1) To prevent partitions from mounting automatically we are going to add their UUIDs to a list via Terminal. First, connect the drives and mount the partitions which you do not want to mount automatically in future. 2) Next, launch Terminal (found in /Applications/Utilities, or with Spotlight). At the prompt, paste the command.

To do this, you will need basic understand of how to enter Terminal commands and use vi.


1) Make sure the disk you want to prevent mounting at boot is mounted.

Dmg

2) Launch Terminal.

3) Run the following command to print out information about the disk:

diskutil info /Volumes/<volume that shouldn't be mounted>

4) Locate the line that starts with: Volume UUID:. Select the UUID (Universal Unique Identifier) that follows on the rest of the line. It will be something that looks like FF9DBDC4-F77F-3F72-A6C2-26676F39B7CE. Your value will be different

5) Copy the UUID to the clipboard.

6) Navigate to /etc by typing the following and pressing enter:

cd /etc

7) Edit (or create) an fstab file by typing the following and pressing enter:

sudo vifs

8) Enter the following line, substituting the UUID you copied in step 5). (Note: vifs uses the value of the EDITOR environment variable to pick the text editor to use. This article assumes you are using the default value of vim.) In vim, the editor starts in command mode. To add a new line, use the arrow keys to move to the end of the document and press the o key to append a new line and enter edit mode. Then type the following:

Mac Os X Dmg File

UUID=FF9DBDC4-F77F-3F72-A6C2-26676F39B7CE none hfs rw,noauto

and press the return key.

9) Type escape to return to command mode and then type ZZ (shift key down) to save and exit vifs (or some other method to save and exit if you are using something other than vim).

10) Type the following and press enter to reset the auto mounter:

sudo automount -vc

11) Quit Terminal


Now, the next time you restart, or unplug the drive in the case of an external drive, that volume will not be mounted. All you have to do is launch Disk Utility, select the grey, disabled volume, and click the Mount button.


You should be able to use a different text editor than vifs if you want. It needs to be able to edit and save files owned by root.

Prevent Mac From Mount Dmg On Startup Windows 10


Note: If all of your disks are encrypted, there is an easier method. For any disk that you don't want to automatically mount, simply don't save the password to the keychain.

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Kelly Heffner Wilkerson
November 8, 2019 at 6:30 AM
Categories: macOS View Comments


I ran into an interesting macOS error while working with a customer a couple of weeks ago. I didn't find a lot of good search results addressing the issue, so I decided to write up a post about it myself.

The error was as the screenshot above shows; trying to open a dmg (disk image), macOS showed the error 'no mountable file systems'. If you see the 'no mountable file systems error' while opening a dmg, here's what you should try:

  1. In most cases, the downloaded dmg file is actually corrupt or had an error downloading. If possible, try downloading the dmg again, turning off any download assistant plug-ins you may have. You can try downloading the file in a different browser as well. Or if you don't need to be logged in to the site to download the file and you want to be fancy, you can try curl -O url in Terminal to download the file. (There's an example of that in my screenshot below.)

  2. Reboot your Mac if you haven't already tried that. Apparently there is an issue sometimes after opening too many dmg files, that is fixed with a reboot.

  3. Try mounting the DMG on the command line in Terminal. We will at least get some sort of useful error message to go on if it still fails:

    • Open Terminal: In Spotlight, the search magnifying glass at the upper right corner of your screen, search for Terminal, and press enter to open the Terminal app. Dmg audio number of liscenses.

    • Type hdiutil attach -verbose into the terminal. Add a space at the end, but don't press enter yet.

    • Drag the dmg file from your Finder window onto the Terminal window and let go. This will fill in the location of the dmg file into your Terminal window.

    • Press enter.
  4. macOS Sierra (10.12) and earlier is not able to mount the new Apple File System (APFS). So if you're on macOS Sierra (10.12) or earlier and you ran hdiutil and see references to Apple_APFS or error 112, the issue is likely legitimate incompatibility, and this disk image won't open on this Mac without an update to the operating system.

    Here's an example of the end of hdiutil attach -verbose output that shows an APFS error due to an older version of macOS:

  5. Think about if you have any kind of security policies on this machine to prevent writing to external drives (thumb drives, optical drives, etc). I haven't seen this one in action, but I read about this being a possibility while researching the issue.

  6. Another suggestion added by a reader (thank you, Markus!) is that filesystem errors on your main Mac drive could be the cause of the disk image mounting errors. Here are instructions from Apple for scanning and repairing errors using Disk Utility. Note that in order to scan and repair errors on your main Macintosh HD drive, you'll need to reboot your Mac into recovery mode. You'll want to choose Disk Utility in the utilities listed in the recovery mode menu.

  7. A new discovery from a reader (thank you, Colby!) is that APFS DMGs won't mount if you're booted in macOS booted in Safe Mode. (Who knew!?!) If you're not sure if you're in safe mode, select the Apple menu  > About This Mac > System Report button, then select the 'Software' heading from the left column. To exit safe mode, restart your Mac, without holding Shift during startup. Or, if you previously set your Mac to always boot into safe mode using nvram, turn off safe mode and have your Mac boot normally on the terminal:

    • Open Terminal: In Spotlight, the search magnifying glass at the upper right corner of your screen, search for Terminal, and press enter to open the Terminal app.

    • Type/paste sudo nvram boot-args=' and press enter.

    • Restart your Mac.