.Net framework 2.0 upper version already has supported ReplyTo property for MailMessage class. But how to set this header to your MailMessage in .Net 1.1, here is what i found, hope it useful for you ^^.
How do I add the Reply-To header to the MailMessage?
How do I add the Reply-To header to the MailMessage?
To add the Reply-To header to an email, you need to use the MailMessage.Headers property. For example:
[ C# ]
[ VB.NET ]
mail.Headers.Add( "Reply-To", "alternate_email@mycompany.com")The following code snippet demonstrates this technique.
[ C# ]
MailMessage mail = new MailMessage();
mail.To = "me@mycompany.com";
mail.From = "you@yourcompany.com";
mail.Subject = "this is a test email.";
mail.Body = "this is my test email body.";
mail.Headers.Add( "Reply-To", "alternate_email@mycompany.com" );
SmtpMail.SmtpServer = "localhost"; //your real server goes here
SmtpMail.Send( mail );
[ VB.NET ]
Dim mail As New MailMessage()
mail.To = "me@mycompany.com"
mail.From = "you@yourcompany.com"
mail.Subject = "this is a test email."
mail.Body = "this is my test email body."
mail.Headers.Add("Reply-To", "alternate_email@mycompany.com")
SmtpMail.SmtpServer = "localhost" 'your real server goes here
SmtpMail.Send(mail)
From www.systemwebmail.com FAQ