SocketTools Secure Library Edition 

The SocketTools Secure Library Edition API has over 800 functions which can be used to develop applications that meet a wide range of needs. SocketTools covers it all, including uploading and downloading files, sending email and much more.
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SocketTools Secure Subscription 

The SocketTools Secure Subscription plan includes Windows dynamic link libraries (DLLs), ATL-based COM objects and ActiveX controls (OCXs) which can be used in a wide variety of programming languages such as Visual Basic and Visual Studio.NET.
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CliMail 

CliMail is a set of command line utilities designed to send and receive email. Send plain-text or HTML (with embedded pictures) email with attachments using to, bcc, and cc recipients. List, display or delete email from POP3(S) or IMAP(S) mailboxes
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