What’s new in this release? Aspose.Network for .NET (version 3.9.0.0) now supports S/MIME protocol which enables you to digitally sign your email messages. About Aspose.Network for .NET Aspose.Network is a suite of .NET components for network programming with support for .NET logging framework, Microsoft Exchange Server and allows parsing ...

 Most likely your CDONTS solution works on a standalone computer because the native Windows Server has SMTP installed as a part of its IIS setup.  The Citrix IIS installation probably doesn't have SMTP installed because it's using MS Exchange for mail delivery.  You need to either install SMTP on the Citrix server's IIS ...