In older versions (e.g. 23.11.) MailMessage had an encrypt method that took an array of X509Certificate2 as parameter so we were able to encrypt a MailMessage for multiple recipients.
It seems the API has changed in new…...-KeyLength 2048 ` -KeyExportPolicy Exportable ` -NotAfter (Get-Date).AddYears(10)...-String "1" -Force -AsPlainText Export-PfxCertificate -Cert $cert...