I recently was going through forum of technetnepal.net and at that moment i just got new that in Windows vista and Windows 7 there is no SMTP service included with FTP services of IIS. Here SMTP service used to ship with IIS 6.0. However, IIS 7.0 does not ship a SMTP service.
After scouring around on the web and trying various SMTP service solutions, the one that I found to be pretty simple to install and configure is hMailServer. Just like the old SMTP that ships with IIS 6.0, hMailServer allows one to restrict access to the local machine (127.0.0.1) only in order to prevent being vulnerable to spam. i.e. I have to use the Third party tool to enable SMTP service in my Windows vista and Windows 7
Some pointers on ensuring you restrict access to your local machine only.
Firstly, only allow SMTP protocol.
Next ensure that you restrict the IP address to the local host.
There are various other settings that can be tweaked, but out of the box with the above recommended settings should work well.
for windows 8 click on this link