Hi @Simon Shaw ,
I understand that you are having an issue adding an MPN ID, even though you have the correct permissions and roles for the tenant, and you are seeing the following two errors:
Location: The MPN ID you provided (mpnid) does not exist, or you do not have access to it. Please provide a valid MPN ID and try again. Please refer to this link for additional information.
Global: You are unable to add a verified publisher to this application. Please contact your administrator for assistance. Please refer to this link for additional information.
There are a few things to check if you have not done so already:
1) Make sure that MFA is enabled on the account. Since you are the admin of the account, you can follow the steps to enable MFA or make sure that security defaults are enabled. You can then go to aka.ms/mfasetup to configure your MFA methods.
2) Then, I would verify that your MPN associated with Azure AD and the current directory are same. You cannot associate an MPN with different directory other than one approved.
As long as you created the App Registration where the domain is primary domain (used to verify MPN ID in the Partner Center), and enabled MFA for the user who is trying to add MPN ID to Application, you should be able to resolve this issue.
I don't think this applies to your situation based on the error messages you included, but I will also note that you can get blocked if your account has been identified as a "risky user." If the user is on the “risky users” list, youmay need to perform remediation steps to eliminate user risk. Reference: Remediate risks and unblock users in Azure AD Identity Protection | Microsoft Learn. After remediating, it will take several hours to invoke dismiss process in our backend, and then you can try adding the MPN ID again.
Let me know any of these steps help resolve the issue and if you still have trouble.
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