How to disable MDM/DEP notifications from macOS Big Sur to Sonoma

This post will allow you to disable/prevent MDM/DEP Notifications and macOS POPUPS forcing you to join an organization's MDM.  This would be handy if a computer was purchased and not removed from Apple's MDM.

Restart the mac in Recovery Mode Restart your Mac then hold down the Command + R keys together until you're in the Recovery Mode

From the menu bar Click on Utilities then select: Startup Security Utility

A popup appears with 3 choices; select (No security) and restart
NOTE:  There is no confirmation notification or button to press

When the system reboots hold down Command + R to get back into Recovery Mode.

Click on Utilities from the top menu bar then select Terminal

In terminal type: mount then press enter/return

A list of devices will show up in a list.  You will want to use the volume that specifically says "/Volumes/Macintosh HD"

In my case it is /Volumes/Macintosh HD (/dev/disk3s4) 

NOTE: it's not "/" (root), and it's NOT /Volumes/Macintosh HD - Data

In Terminal Write:

1. umount /Volumes/Macintosh\ HD
2. mkdir /Volumes/Macintosh\ HD
3. mount -t apfs -rw /dev/disk3s4 /Volumes/Macintosh\ HD
4. cd /Volumes/Macintosh\ HD/System/Library/LaunchAgents
5. mkdir xtemp
6. mv com.apple.ManagedClientAgent.* xtemp/
7. mv com.apple.mdmclient.* xtemp/
8. cd ../LaunchDaemons
9. mkdir xtemp
10. mv com.apple.ManagedClient.* xtemp/
11. mv com.apple.mdmclient.* xtemp/
12. csrutil authenticated-root disable (this will Turn off Signed System Volume SSV)
13. bless --folder /Volumes/Macintosh\ HD/System/Library/CoreServices --bootefi --create-snapshot
 (this will Save the current disk status in the boot snapshot)

Now you can restart your Mac, and DEP notifications are disabled.

Creating a MacOS administrator account when none exists

An easy and safe way create an administrator account when non-exists on MacOS is to boot into single user mode and mount the OS drive. We actually want to delete a file called the .AppleSetupDone file located in /var/db. This will cause the user wizard to run again where you can create any kind of account again after you exit or reboot out of single user mode including an administrator account.

Here are the steps:

1. Turn on your mac pressing the "command ⌘" key + S. This will boot you into Single User Mode
   
2. Mount the drive by typing /sbin/mount -uw /
   
3. type rm /var/db/.AppleSetupDone
   
4. type exit or reboot and it will run the account setup wizard and setup the administrator account

Create a USB Bootable Disk on OS X

To create a bootable USB Disk in Mac OS X, You must have the Application of the version of Mac OS X that you want to install downloaded and extracted.  Please make sure you have a mac and root access before proceeding.

So for this example we are going to use macOS Sierra.  You must have the "Install macOS Sierra.app" and if your looking for step by step instructions it must be downloaded into your Applications Folder.

To download an older version of MacOS from Yosemite to Catalina, you can download the MacOS App using this url https://support.apple.com/en-us/HT211683

Plugin a Flash Drive; I'm going to use a Verbatim 16GB USB Flash Drive. Open /Applications/Utilities/Terminal.app

sudo /Applications/Install\ macOS\ Seirra.app/Contents/Resources/createinstallmedia --volume /Volumes/STORE \N \GO --applicationpath /Applications/Install\ macOS\ Seirra.app --nointeraction

You can modify this command line to use with any previous version of OS X if you can get a copy of the Install.app and replace the bolded text with the previous version of the OS X install.app  for example "Install\ OS\ X\ El\ Capitan" and you must put \ $text so the mac can recognize spaces in the name.  The \ is an "escape" and tells the OS that there is a "space" character.

***UPDATE***

You can find this on apple's knowledge base for the issue but they removed the application path for the USB installer.

sudo /Applications/Install\ macOS\ High\ Seirra.app/Contents/Resources/createinstallmedia --volume /Volumes/STORE \N \GO

https://support.apple.com/en-us/HT201372

***Pre High Seirra***

sudo /Applications/Install\ macOS\ Seirra.app/Contents/Resources/createinstallmedia --volume /Volumes/STORE \N \GO --applicationpath /Applications/Install\ macOS\ Seirra.app --nointeraction

Below is the log from my terminal screen.  This could take up to 10 - 30 minutes depending on your system, and if may have to make adjustments if your file system is case sensitive or not.

sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/STORE\ N\ GO --applicationpath /Applications/Install\ macOS\ Sierra.app --no interaction

Erasing Disk: 0%... 10%... 20%... 30%...100%...

Copying installer files to disk...

Copy complete.

Making disk bootable...

Copying boot files...

Copy complete.

Done.

At the end of this you will have a bootable USB device that you can do a system recovery, disk image, or a fresh install of your mac with.

Enabling Trim on 3rd Party SSD on MacOS

Solid State Drives or SSD's as they are commonly referred to are now the easiest and cheapest way to bring new life to your old computer.  Many of the SSD's max out the bandwidth provided by the bus that your computer connects to the hard drive.  On MacOS though if your lucky enough to have an older mac then you can upgrade with any SSD you would like but what you don't know is that Apple doesn't enable TRIM by default even though most SSD's support TRIM. 

Why do you want Trim?  I'm not going to go into it in detail because Techspot has a great article you can read in detail here

Basically SSD's can not directly over write cells with new data, but must first be erase it at the block level.  This is called garbage collection.  The flash memory uses over provisioning used to improve performance and longevity of the SSD.   

The less space not consumed by your data becomes what is called dynamic over provisioning – because it changes as the amount of data stored changes.  When less data is stored by the user, the amount of dynamic over provisioning increases, further improving performance and longevity.

Here is what you need to do to enable Trim on your SSD on your Mac.

1. Close all programs except for Terminal if you

First you can check and see it if Trim is enabled.  You can do this 2 ways.

Terminal.

system_profiler SPSerialATADataType | grep 'TRIM'

You will get a response of TRIM Support: Yes or No

Or go under the Apple Menu -> about this Mac -> and run System Report

If you get a Yes you don't need to do anything trim is enabled.

If you get a No type the following command.

sudo trimforce enable

Then answer yes to the two questions and it will reboot.

Trim will be enabled after the reboot.  You can verify this by using the terminal command

system_profiler SPSerialATADataType | grep 'TRIM' or checking the system report.