CDO.Message error.

Hii,
   I need some help with CDO.Message mail generation.
  when my mail application is executed i am recieving an error saying,
  "System.IO.FileNotFoundException: The specified protocol is    unknown."
  The line that is generating the error is,
  msg.CreateMHTMLBody("maildes.aspx",CDO.CdoMHTMLFlags.cdoSuppressNone," "," ");
   This is for the first time that i am working on mail generation,So any kind of help is Appreciated.
  Thank you.



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