Windows Server 2003 introduced a POP3 component, which, along with the already existing SMTP component made a complete Email Server on Windows. But this combination was never adapted widely due to various limitations. Specifically the SMTP component lacked most security features needed for any robust mail server. Microsoft did not make the built in SMTP and POP3 components feature complete for obvious reasons. Doing so would make Exchange Server a less attractive solution. Windows 2008 completely dropped the POP3 component!
Fortunately, there are several great Email solutions available on Windows today, and some of them are completely free! Searching for free Mail Server for Windows however is a little tricky. It is because every commercial software offers 'Free Downloads' and the search engines have a hard time in distinguishing 'Free Mail Server' from 'Free Download of a Commercial Product'. I am going to list a few Email Servers for Windows that I am familiar with, just in case you were looking for a reliable but free Email solution on Windows.
List of Free Email Servers for Windows
- One of the two Open Source Mail Servers for Windows!
- Windows only, not cross platform.
- Features many security and filtering options
- Long and active development.
- Uses SQL server or MySQL Server as mail storage.
- Does not include a Webmail interface, but you can use any POP3 or IMAP compatible Webmail solution with it.
- Very easy to install and configure.
- Another Open Source and Free Mail Server for Windows.
- Multi platform, also available on Linux/Unix etc.
- Very stable, long and active development.
- Configuration is via tab delimited files, and may require some learning.
- Webmail not included, use your own.
- In my opinion, not as feature rich as the hMailServer, but still a very good option.
- Free version of a commercial software.
- No limitations on the number of Users or Domains. However, many advanced features are not available in the free edition.
- Webmail, IMAP and Anti-SPAM features not included.
- Free edition of this commercial software allows one domain with unlimited users.
- Feature rich.
- Developed with .NET, with Web based administration and Webmail, Web Services etc.
- Active development, now coming with version 5.x.
- Free for non commercial use.
- Also available for Novel Netware.
- Feature rich, developed by the creator of Pegasus Mail Client.
- SMTP, POP3 and IMAP, but no Webmail.
- I have no personal experience with this one.
Some of these Free Email Servers are supported by popular hosting control panels.
You may also want to check out Macallam Mail Solution for Windows, which is a relatively new product but seems promising. The free edition has allows a maximum of 128 user accounts.