Mac does not boot: Unrecoverable error by TeamViewerAuthPlugin: start

Unrecoverable Error: When the Mac no longer boots

A reader wrote to me today that her Mac no longer boots after throwing TeamViewer off the disk. What exactly happens is the following: The Mac boots, but does not start up because an error message appears beforehand, which can only be acknowledged with OK. The exact message is:

Unrecoverable error. SecurityAgent was unable to create requested mechanism TeamViewerAuthPlugin: start.

Reinstalling macOS is unsuccessful

My first idea when faced with such problems is to boot the Mac into recovery mode using CMD + R and then install macOS Catalina over it. Unfortunately, this "trick" has no effect in the present case. For that reason we must look for other solutions.

Incidentally, starting in safe mode (with the SHIFT key pressed) does not help. The Mac still does not boot.

Unrecoverable Error: If TeamViewer is not uninstalled properly, the Mac may no longer boot.
Unrecoverable Error: If TeamViewer is not uninstalled properly, the Mac may no longer boot.

What is the cause of the error?

To clarify how the matter can be resolved, it is often helpful to know why the error arose in the first place. As I could read in various forum posts - even in the TeamViewer forum - it is not a good idea to simply drag the TeamViewer app from the programs folder to the trash in order to uninstall it.

Instead, it is recommended to go to Settings> Advanced> Uninstall in the app itself, as in this case all data will also be removed from the system folders. Failure to do this can lead to the above problem.

Mac panic due to the authorization plug-in not being found

In one case, this occurred because a user deleted TeamViewer using CleanMyMac, which removed all data associated with TeamViewer. In detail: TeamViewer registers an authorization plugin during installation, but it was not de-registered when the corresponding data was removed. For this reason, macOS expects to load the plugin on boot, but does not find the "TeamViewerAuthPlugin.bundle" file in the "/Library/Security/SecurityAgents/" folder and panics.

Note: I cannot give any guarantees as to the reliability or security of the steps described here. What you do is at your own risk and I am not responsible for any damage or loss of data. However, if all goes well, you should be able to restart your Mac after the procedure.

In both instructions you have to boot the Mac into recovery mode. To do this, hold down CMD + R when restarting (Photos: Sir Apfelot).
In both instructions you have to boot the Mac into recovery mode. To do this, hold down CMD + R when restarting (Photos: Sir Apfelot).

I got the following two instructions from English From this page translated.

Solution 1: Remove the authorization database

With this approach, the auth.db is deleted so that the Mac can create it again.

  1. Boot into recovery mode
    1. Restart your Mac and hold the keys cmd + r until the logo appears. This may take a moment - be patient.
    2. Once inside, choose language, username and enter your password (didn't need it for me). Follow the instructions until you see the "macOS utilities" see.
    3. Choose "Disk Utility' in this window.

      In the macOS utilities, select the hard disk utility to check whether the hard disks are mounted or activated.
      In the macOS utilities, select the hard disk utility to check whether the hard disks are mounted or activated.
  2. Activate the hard drives
    1. In Disk Utility, in the left column under "Internal" the hard disk "Macintosh HD' and then in the right pane click 'Enable". (see tips 3 and 4)Tip 1-1: If you are asked for a password when activating, enter your login password.
      Tip 1-2: The hard drive may already be activated. If you mark the hard disk on the left and a "Disable" button appears on the right and a colored info bar is visible, this means that the hard disk is already activated.
      Tip 1-3: The name of the hard disk may be different than in this example. However, the offense is the same.
  3. Open that Port
    1. To make sure the hard drives are enabled, go to the menu bar, go to "Utilities' and then select 'Port".
    2. Enter the following command: ls /Volumes/. This command lists all activated hard drives.
    3. You should name your main hard drive(s) like "Macintosh HD' in the list. About:
      Macintosh HD/ Macintosh HD - Data/Tip 1-4: The number of entries (hard drives) and their names may be different on your Mac

      In addition to the Macintosh HD and Macintosh HD data, I also displayed the other external hard drives.
      In addition to the Macintosh HD and Macintosh HD data, I also displayed the other external hard drives.
  4. Delete the file
    1. Enter the following command in the terminal:
      rm "/Volumes/Macintosh HD/var/db/auth.db"Tip 1-5 - Very important: The command above will delete the "auth.db" file. Because of this, you need to be sure you're specifying the path in the correct format. So:
      a) Remember that the command is case sensitive. This means, for example, that "macintosh" is different from "Macintosh".
      b) Make sure there is a space between "rm"and the Path is, just like between "Macintosh"And"HD".
      c) The path should be enclosed in double quotes "".

      Tip 1-6: Any error message like "No such file or directory" or "Read-only file system" means there is an error in the file path. So before you call for help, take a deep breath and double-check the command you entered against the command above. Then you will surely find the error.

  5. Überprüfen
    1. If that is successful, you will not get any congratulations. Don't take it personally!
    2. To make sure the file is deleted, enter the following command. He should not Output "auth.db" as the result.
      ls "/Volumes/Macintosh HD/var/db/auth.db"Tip 1-7: If the file is still there, it means you made a mistake - probably in the file path. Repeat step 4 again and this time make sure that you type everything exactly as it is in these instructions.

      Here you can see the auth.db file that we want to delete.
      Here you can see the auth.db file that we want to delete.
  6. restart
    1. If the check was successful, don't rejoice too soon, because now you have to restart your Mac - and keep your fingers crossed!
    2. To restart the Mac, go to the Apple icon in the top left and choose Restart from the menu. Then wait for the Mac to restart.
    3. If you can make it back to login, then
      1. enter your password
      2. close your eyes
      3. press return
      4. give the Mac a minute and (only then!) open your eyes ... don't cheat!
      5. when he booted cleanly, come back to my page and share your feeling ... ;-)

Solution 2: copy file from another Mac

Another way to get the Mac to boot again is to copy the missing file back into the appropriate folder. However, this requires a second Mac on which TeamViewer has been installed. If you don't have a second Mac, you should choose solution 1.

  1. Obtain missing file
    1. Install TeamViewer on another Mac.
    2. Copy the "TeamViewerAuthPlugin.bundle" file from /Library/Security/SecurityAgent/ to a USB stick.
      Tip 2-1: The stick must first be formatted as "Mac OS Journaled with upper and lower case" in Disk Utility.
  2. Boot Mac into Recovery Mode
    1. Start the Mac and hold the CMD + R keys until the Apple logo appears. This may take a while, please be patient.
    2. Once you're in recovery mode, you choose a language, username, and password, and you're taken to the macOS Utilities window (note: I didn't have to type anything on mine).
    3. In the "macOS Utilities" window, select "Disk Utility".
  3. Mount or activate the hard drives
    1. Now you plug the USB stick into the Mac.
    2. In Disk Utility, select the "Macintosh HD" hard disk under "Internal" in the left area and click on the "Activate" button in the bar at the top right (note: the disks were already activated in my case).
    3. In the left area under "External" select the USB stick and also click on "Activate".
      Disk Utility will verify that the Macintosh HD is activated. If this is the case, there is the "Deactivate" button at the top right. Otherwise "Activate" would be written there.
      Disk Utility verifies that the Macintosh HD is mounted. If this is the case, there is a "Disable" button in the top right corner. Otherwise it would say "Activate".

      Tip 2-2: If you are asked for a password when mounting, you enter the login password.
      Tip 2-3: The USB stick may already be activated. In this case you will see the button "Deactivate" instead of "Activate". In this case, the info line is colored, which means that the drive is activated.
      Tip 2-4: The name of the hard drive or the USB stick can vary.

      The terminal can be found via the "Utilities" menu.
      The terminal can be found under the Utilities menu.
  4. Open the terminal
    1. If you are sure that the hard disk and the USB stick are mounted, select under "Utilities" the app "Port' and start it.
    2. Enter this command:
      ls /Volumes/
      This shows all activated volumes.
    3. You should see the name of your flash drive in the output, e.g. "MyUSB", lined up with the name of your internal hard drive, e.g. "Macintosh HD".
      MyUSB/ Macintosh HD/ Macintosh HD - Data/
      Tip 2-5: The number of entries and their names may differ from the example here, but it should match what is discovered in Disk Utility.
  5. Copy the file
    1. Enter the following command in the terminal (see tip 10):
      cp -r "/Volumes/MyUSB/TeamViewerAuthPlugin.bundle" "/Volumes/Macintosh HD/Library/Security/SecurityAgentPlugins/"

      Tip 2-6 - very important:
      The command above copies the missing file from the USB stick to the Macintosh HD hard drive. For this reason you have to make sure that you have given the correct file path:
      a) Remember that the command is case sensitive. So "myusb" is something different than "MyUSB".
      b) spaces are important. For example, there is a space between "cp" and "-r" or between "Macintosh" and "HD" or between the first and second file paths.
      c) Both paths should be enclosed in double quotes "".
      Tip 2-7: Any error message like "No such file or directory"Or"Read only file system", means either the first or second path was not specified correctly. Before you ask for help please check twicewhether you have specified the paths correctly.
  6. Testing
    1. To make sure the file was copied correctly, enter the following command. The output should be the file "TeamViewerAuthPlugin.bundle' (see note 10)
      ls "/Volumes/Macintosh HD/Library/Security/SecurityAgentPlugins/"
      Tip 2-8: If the file cannot be found, it means you made a mistake. Probably with the paths in the command to copy. Please start again at step 4 and check the entries carefully.
  7. restart
    1. Once the copy process is verified, don't rejoice too soon, because now you have to start your Mac and keep your fingers crossed.
    2. To initiate the restart, go to the Apple menu in the top left and select "Restart". Wait for the Mac to finish.
    3. If you can make it to the login screen, then:
      1. enter your password
      2. close your eyes
      3. press return
      4. give the Mac a minute and (only then!) open your eyes ... don't cheat!
      5. when he booted cleanly, come back to my page and share your feeling ... ;-)

    Tip 9: Please take your time and follow the instructions carefully to avoid making a mistake.
    Tip 10: All commands should be entered in one continuous line. The spaces and special characters such as “/” and “\” must also be taken into account.

Does the Mac boot again? Your tips are in demand!

If the instructions helped to solve the problem, I would be happy to hear from you. If it didn't work for you, please write to me at which step it hangs. I will then gladly try to help you.

Did you like the article and did the instructions on the blog help you? Then I would be happy if you the blog via a Steady Membership or at Patreon would support.

42 Responses to "Mac won't boot: Unrecoverable Error by TeamViewerAuthPlugin:start"

  1. Martin Schellmoser

    Exciting thing and good to know. As always, many thanks for the detailed tutorial! And remember: Always uninstall TeamViewer properly. Only one thing is not clear to me: How can TeamViewer (installed in the conventional way) penetrate so deeply into the system that normal start-up is no longer possible? Past gatekeepers and SIP? That is certainly not intended by Apple ...

    1. That's a good question. I guess during the installation you will be asked for the admin-PW and then the evil starts. I'd rather be by now AnyDesk tend ... that doesn't make such nonsense.

      1. You are great thank you very much
        There is no other site where anyone comes close to describing it in as much detail and aptly.

        You safed my Mac and my day by the way ;)

        1. Many thanks... I panicked for a moment when the error message appeared.
          With your very detailed and perfect instructions, I was finally able to restart my Mac again... I would never have been able to do this on my own...
          Thanks again

  2. Thank you, thanks to your description, I got my Macbook back.
    A question, how can I completely delete Teamviewer so that something like this doesn't happen again? Lg Aleyna

    1. Hello Aleyna! This is only possible via the TeamViewer software itself: There you go to Settings> Advanced> Uninstall. Then the software is completely removed.

  3. Hello, I have the same problem. However, I cannot follow your steps because I cannot restart my Mac at all because the power button on my touchbar is missing. Can you help me?

    1. Hello Eray! What kind of mac do you have And where is the power button? The location doesn't really matter for the instructions ... you just have to hold down the power button for a long time. Then it reboots.

  4. Hello, first of all thanks for the instructions.
    Despite correct input, I always get "illegal option" when I enter the command.
    – A difference I could find: When I display the volumes, it still comes up for me
    "Macintosh HD USB name
    Macintosh HD – Data mac OS Base System”
    but never all three in one line like you do. Could that be the cause of the error?
    How can I fix this?
    Thank you very much !

    1. Hello Ric! I'm strongly betting that the macOS structure on the hard drive has changed since the writing of the article. Since I don't know how to customize it, I would suggest you this "detour".
      1. Install Teamviewer again
      2. Call up the TeamViewer settings
      3. Open the "Advanced" tab
      4. Under Uninstall, click the Uninstall button
      5. TeamViewer will be uninstalled

      I hope you get on with this.

      1. Oh alright and thanks for the quick reply.
        But how can I reinstall TeamViewer if I can't get past the macOS utility in recovery mode?
        Reinstall MasOS?

        1. Hello Ric! Sorry, I forgot that you can't finish booting. Then we take another way:
          I would say you take an external hard drive, format it to APFS, reinstall macOS on it (via the button you described) and then get the data from the internal hard drive into the new user account. At some point macOS will ask you if it should import a user from elsewhere. Then you have everything running on the external disk (please check!).
          Then you have to do the same thing the other way around: you delete the internal disk, install macOS on it and use user import to import the data from the external disk to the internal disk. If that worked, you no longer need the external hard drive and can keep it as a backup.

      2. oh all right!
        Could you tell me how I can reinstall the program?
        I can't get past the macOS Utilities window.
        Should I click "Reinstall macOS" here?

        Thank you for your help!!!

  5. Hello, I got to this page via google and wanted to give my 2 cents because they might help someone else.
    We had the problem on a MacPro server - I don't quite understand why the error only appeared now, a colleague had probably removed Teamviever while I was on vacation.
    Interestingly, all services were still running, I just couldn't log in with a user anymore. I had no direct physical access to the server, a remote solution had to be found.
    If you have remote access to the server and have AppleRemote desktop, you can easily load a current Teamviewer host, in the Teamviewer Host Installer you will find the file " Install TeamViewerHost.pkg" This can now be installed remotely on the server via AppleRemote Desktop. If you now confirm the "Unrecoverable Error by TeamViewerAuthPlugin:start" error message with "OK" on the faulty server, you can log in again.
    After logging in, I then removed TeamViewer cleanly using its own deinstaller.
    It all worked for me remotely via VPN from another city and saved me a hell of a lot of time.

    1. Hello SebSta! Thank you for your complement. This is interesting and also a good solution to solve the problem!

  6. Anja B Thuesen

    You really are a knight in shining armor! My Mac is running perfectly again! The only obstacle I encountered was that "Port" was called "Terminal" on my Mac and I had to close Disk Utility before the menu bar with "Terminal" was visible. But fortunately that was overcome! Thank you very much!

    1. Jen Kleinholz

      Hello Anja! That makes me happy. Hopefully the Mac will continue to run a little longer without causing any problems. 😊

  7. You really are the hero, explained very clearly, step by step. Everything worked! Thank you so much! If only there were more smart guys like you :-)

    1. While macOS shows it as one file, it's technically a folder with files inside. That's why I saved it for you as a ZIP archive. You would have to unpack that. I hope that macOS will then recognize it as a bundle file again. The file is here for download filed.

  8. Thanks a lot for this! I have a deadline tomorrow and that was the worst possible time to make that mistake. I was sitting on google crying in my room because none of the forums could give me a solution and this worked like a charm. I really appreciate you taking the time to write this and thanks again - you are a life saver!

    1. Hello Ben! Glad the guide was helpful. I didn't think that it would "hit" so many people who would be locked out of TeamViewer. 😊

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