API Type: SMTP Sender.
API Interface: COM Library.
Business Logic: Sending mail via SMTP, read mail via POP3.
Language Support: Any *unmanaged* COM compatible language (C++, VB6, VB Script).
Direct Property Access: N/A.
Product Versions: Windows NT and Windows 2000.
CDONTS was viewed as a subset of CDO 1.21 in Windows NT and Windows 2000. It's primary function is an SMTP mailer API for ASP pages and applications running on a web server with a local SMTP server (including Exchange).
In Windows 2003 support for CDONTS was dropped and CDOSYS CDOSYS should be used in its place. While it is installed with Windows 2003, its not registered by default. It’s was also not supported running under .NET. The path forward is to use an API like CDOSYS or System.Net.Mail – both are considered current APIs.
Introduction to CDO for NTS
Use with Programming Languages:
Managed Code (.NET)
Can Run Under:
Running Under Windows Service
Running Under IIS
Running Under COM+
Running in a Web Service
Send Via MAPI Provider
Sending Via SMTP Pickup
Sending Via SMTP Port
Sending Via Submission URL
Can Save Sent Mail in Sent Items folder
Some Points Of Interest:
Can read POP3 data
Works with Windows NT.
Homework if you wish to know more:
Windows Server 2003 does not install CDONTS
How to migrate the Collaboration Data Objects for NTS applications to Microsoft Collaboration Data Objects for Windows 2000
Support policy for Microsoft Exchange APIs with the .NET Framework applications
Using CDO for NTS
Collaboration Data Objects Roadmaphttp://www.microsoft.com/technet/prodtechnol/exchange/55/maintain/cdordmap.mspx
INFO: What is the Difference Between CDO 1.2 and CDONTS?
Where to acquire the CDO Libraries (all versions)
Description of CDONTS and how to troubleshoot CDONTS problems in Windows 2000 and in Windows NT 4.0
About: SMTP Sending APIshttp://blogs.msdn.com/b/webdav_101/archive/2015/05/28/about-smtp-sending-apis.aspx