Hi @Kani · ADFS on Windows Server 2012 doesn't support Azure MFA which is why it is failing to run New-AdfsAzureMfaTenantCertificate. You need to use either Windows server 2016 or 2019 OS for this to work.
This is documented in below paragraph of this doc: Configure Azure MFA as authentication provider with AD FS
Unlike with AD FS in Windows Server 2012 R2, the AD FS 2016 Azure MFA adapter integrates directly with Azure AD and does not require an on premises Azure MFA server. The Azure MFA adapter is built in to Windows Server 2016, and there is no need for additional installation.
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