The message could not be sent to the SMTP server.

Hi

I get this error when sending emails using my code modules in K2.

I have set the default smtp server name in the K2Server.config file to the name of our exchange server. 

full error msg "System.Runtime.InteropServices.COMException (0x80040211): The message could not be sent to the SMTP server. The transport error code was 0x800ccc15. The server response was not available"

This is the function i'm using;

 Private Function sendServerMail(ByVal K2 As ServerEventContext, _
  ByVal fromAddress As String, _
  ByVal toAddress As String, _
  ByVal Subject As String, _
  ByVal Body As String)
  'send the mail       
  Dim objMsg As New System.Web.Mail.MailMessage()
  Dim objAttachment As System.Web.Mail.MailAttachment
  Dim objSender As System.Web.Mail.SmtpMail
  objSender.SmtpServer = SourceCode.K2Utilities.GeneralMod.GetDefaultSMTPServer()
 
  objMsg.From = fromAddress
  objMsg.To = toAddress
  objMsg.Subject = Subject
  objMsg.Body = Body
  objSender.Send(objMsg)

 End Function

Any ideas