Check whther SMTP service is installed or not

There are any number of ways depending on your situation, which SMTP server, whether it's local or remote.

I suppose the most general is to attempt an SMTP session via a socket.

1) Attempt to open a connection to the server in question on port 25.  If that fails then there is no standard SMTP service on that machine (or it's unavailable to you).

2) If that succeeds, attempt to "talk SMTP" to it.  Probably the easiest thing is to say "HELO" and get the response.

W2003 Server

Click Start - Setting - Control panel - Administrator Tools - Computer Management
If you find Default SMTP Virtual Server under "IIS Manager", your machine has SMTP installed.

Or, you can find in Services - "Simple Mail Transfer Protocol"
Click Start - Setting - Control panel - Administrator Tools - Services

SMTP can be installed based on IIS. If you don't want to use HTTP Services (WEB), you can use only SMTP only, Just stop HTTP Services and just run SMTP Service in the Services Consol.

Other OS like W2000 or NT are very similiar of this configuration.

If you have any problem or concerns about this comments, please let me know. Thanks,

Sewoo,

How can we check this programmatically?

what programming language you prefer here? You can try refer to the link i provided above if you're using VB/VBA/VB.NET

In that link it is checking for sqlserver. I just want to check whether SMTP is installed or not. Can we check it by searching in the Sevices in the control panel. Is there any possibility like installed, but not in Services?

>>Can we check it by searching in the Sevices in the control panel
The codes in the link I provided above is checking the Services in the control panel... what you need to do is change the service name of "MSSQLSERVER" to "W3SVC"

good luck!