As you can read from http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemwebmailmailmessageclasstopic.asp, the required platforms are Windows 2000, Windows XP Professional, Windows Server 2003 family.

Are your users on one of these ?

A good link to know about this namespace is http://www.systemwebmail.com/


>Hi all!
>
>My application is using System.Web.Mail for sending e-mail notices. On my machine where everything is working fine. But on the clients machine, my application works fine until it reaches the point where I use this object. Is there a special something that I need to do in order to for this to work on the client machine?
>
>
>Thanx! in advance 8 )
>
>Martin