MailKit
MailKit is a versatile .NET email client library providing broad protocol support such as SMTP, POP3, and IMAP, built on MimeKit. It includes SASL authentication, proxy support, and SSL/TLS security. The library emphasizes RFC-compliant implementations, offering features like client-side sorting, asynchronous APIs, and cross-platform support. Donations aid in the development of tools like static analysis, beneficial for users seeking a stable email framework.