Use BouncyCastle to sign and encrypt message instead of .NET native Cms provider for RSA-PSS. Send email in C#, VB, CLR, ASP.NET, .NET Core, or other .NET environment applications with SMTP component based on SMTP RFC, Exchange Web Service, WebDav, Gmail API and Microsoft Graph API. SSL, S/MIME, HTML, Gmail OAUTH and Embedded Images are supported.
$ dotnet add package EASendMail.BCNo README available.