cdosys kullanmanı tavsiye ederim asp ile tam senkron çalışıyor örnek kod:

<%
Set ObjSendMail = CreateObject("CDO.Message")
ObjSendMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/sendusing") = 2
ObjSendMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/smtpserver") = "mail.sunucun.com"
ObjSendMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/smtpserverport") = 587 'genelde 587 dir
ObjSendMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/smtpusessl") = False
ObjSendMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/smtpconnectiontimeout") = 60
ObjSendMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/smtpauthenticate") = 1
ObjSendMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/sendusername") = "popepostaadresin@sunucun.com"
ObjSendMail.Configuration.Fields.Item ("http://schemas.microsoft.com/cdo/configuration/sendpassword") = "popşifren"
ObjSendMail.Configuration.Fields.Update
ObjSendMail.To = "kime@kime.com"
ObjSendMail.Subject = "konu"
ObjSendMail.From = "kimden@kimden.com"
ObjSendMail.HTMLBody = "mail içeriği"
ObjSendMail.Send
Set ObjSendMail = NoThing

%>