Can be used in place of ContentID, and is much more friendly when getting the body content of an email from an html file.
According to RFC2557 -- A Content-Location header specifies an URI that labels the content of a body part in whose heading it is placed. Its value CAN be an absolute or a relative URI. Any URI or URL scheme may be used, but use of non-standardized URI or URL schemes might entail some risk that recipients cannot handle them correctly. An URI in a Content-Location header need not refer to an resource which is globally available for retrieval using this URI (after resolution of relative URIs). However, URI-s in Content-Location headers (if absolute, or resolvable to absolute URIs) SHOULD still be globally unique.
EmailMessage msg = new EmailMessage( "mail.mycompany.com");
msg.FromAddress = "me@mycompany.com";
msg.To = "you@yourcompany.com";
msg.Subject="Company Logo";
//add the html bodypart
msg.HtmlBodyPart = "<b>What do you think of the cool new logo?</b><img src=http://whatever/images/CompanyLogo.gif>";
//embed and add the embedded object
EmbeddedObject o = new EmbeddedObject();
o.Name = "logo.gif";
o.ContentType= "image/gif";
o.ContentLocation = "http://whatever/images/CompanyLogo.gif";
o.FilePath = "logo.gif";
msg.EmbedObject( o );
msg.Send();
Dim msg As EmailMessage = New EmailMessage("mail.mycompany.com")
msg.FromAddress = "me@mycompany.com"
msg.To = "you@yourcompany.com"
msg.Subject = "Company Logo"
'add the html bodypart
msg.HtmlBodyPart = "<b>What do you think of the cool new logo?</b><img src=http://whatever/images/CompanyLogo.gif>"
'embed and add the embedded object
Dim o As EmbeddedObject = New EmbeddedObject()
o.Name = "logo.gif"
o.ContentType = "image/gif"
o.ContentLocation = "http://whatever/images/CompanyLogo.gif"
o.FilePath = "logo.gif"
msg.EmbedObject(o)
msg.Send()