Summary
To enhance security, exporting the Auth certificate and its private key by using the Export-ExchangeCertificate cmdlet is no longer supported. This update blocks this functionality. If it's necessary to export the Auth certificate together with its private key, you should use the Windows PowerShell Export-PfxCertificate cmdlet or use the MonitorExchangeAuthCertificate.ps1 script. This cmdlet must be run directly on the server that's running Exchange Server. For more information, see Export-PfxCertificate.
Resolution
To fix this issue, install the following security updates, as appropriate:
