Hello johnsmith-3681,
Thank you for posting in our Q&A forum.
Here is the answer for your references.
We recommend that you put the machines that need to apply the LAPS password in an OU and then deploy LAPS just as you did in the test environment.
Because the default "Computers" container is a container not an OU, and you used the command "set-admpwdcomputersself permission -orgunit computers", I think "-orgunit" in the command should follow an OU instead of a container.
Q: Is there a way to apply this permission to the whole domain?
A: If you must want to deploy these permission in domain wide, you can try the following commands to see if it helps.
Set-AdmPwdComputerSelfPermission -Identity "DC=DOMAIN,DC=com"
Set-AdmPwdReadPasswordPermission -Identity "DC=DOMAIN,DC=com" -AllowedPrincipals "LAPSAdmins"
Set-AdmPwdResetPasswordPermission -Identity "DC=DOMAIN,DC=com" -AllowedPrincipals "LAPSAdmins"
Her is a similar thread.
https://social.technet.microsoft.com/Forums/en-US/13c23379-3a08-416c-a7f6-43caa7c507a9/laps-deployment-to-the-whole-domain
Tip: If you deploy LAPS in the domain wide, please make sure the LAPS does not apply on Domain Controller machines.
Other references for deploying LAPS.
https://theitbros.com/deploying-local-administrator-password-solution-laps-in-active-directory/
https://www.prajwaldesai.com/how-to-install-and-deploy-microsoft-laps-software/
Hope the information above is helpful.
Best Regards,
Daisy Zhou
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