Hello @Yu-Jeong Seo Thank you for posting your question on the Microsoft Q&A platform. Happy to assist!
The error message "Invalid email address or authentication type was provided. Please enter a valid email address or choose the right authentication type to add the user" typically occurs when you are trying to add an enterprise administrator account in the Azure portal and the email address or authentication type is incorrect.
To resolve this issue, please ensure that you are entering a valid email address for the enterprise administrator account. Also, make sure that you have selected the correct authentication type for the user.
Check that you have sufficient permissions to add enterprise administrator roles. Typically, this requires global administrator or privileged role administrator permissions in Azure AD.
If you are not the global administrator, coordinate with someone who has appropriate permissions to perform the role assignment.
If you are still having trouble, you can try adding the enterprise administrator account using PowerShell or Azure CLI. This will allow you to specify the email address and authentication type more precisely.
Here's an example PowerShell command to add an enterprise administrator account:
New-AzureADUser -DisplayName "John Doe" -UserPrincipalName "johndoe@contoso.com" -Password "P@ssw0rd" -MailNickName "johndoe" -AccountEnabled $true -UsageLocation "US" -OtherMails "johndoe@contoso.onmicrosoft.com" -ImmutableId "johndoe@contoso.com"
Make sure to replace the values with the correct information for your enterprise administrator account.
If these steps doesn't help you resolve the issue, the best option would be to contact Azure technical support team by raising a support ticket. The ticket enables you to work closely with the support engineers and get a quick resolution to your issue.
Here is the link - https://docs.microsoft.com/en-us/azure/azure-portal/supportability/how-to-create-azure-support-request to create support case.
Hope this helps!
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