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October 9, 2005

Mail Component Q/A - Junk Email, Message-ID, Custom Headers


  1. How do I prevent emails sent from going into the receiver’s Junk Email folder?
  2. How do I set the Message-ID header?
  3. How can I add additional headers?


  1. It’s not under your control. External mail servers and the filtering done by the receivers mail client determine what is classified as junk.
  2. Call AddHeaderField("Message-ID","newValue"). Also, be sure to set the mailman.AutoGenMessageId property = false because the Message-ID field is somewhat special. Chilkat automatically generates a new message ID with each email to prevent SMTP servers from dropping emails mistaken as duplicates. What happened in the past was that Chilkat customers would re-use the same email object without changing the Message-ID. The first email is sent OK, but subsequent emails are not because the SMTP server perceives them to be duplicates because of identical message IDs.
  3. Call emali.AddHeaderField.

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