Duplicate email addresses in an email

What happens when an email message includes same recipient address twice? Either both in the TO or the CC line, or once in each. What if the address is buried in a distribution group?

Does it depend on any (or all) of the following:

  • Client program sending the message
  • SMTP server receiving the message from the client
  • Intermediate servers (ones between SMTP sever, and the recipients Exchange/POP/IMAP server)
  • recipients Exchange/POP/IMAP server
  • recipients email client

This is Epicor related, as we have some automated emails, with a static list of addresses in the CC list for all emails. However, the project manager of this order (who is in the CC list), is set in the TO list. - and should not be in the CC list also.

Since my email is built in code, I do a search and replace to remove name from the CC list, if it’s being added to the TO list.

But whenever the list of people to be CC’d changes I have to edit code (just a var declaration, but a pain none the less). So I was going to just have the CC List be distribution group, and then someone else would maintain the distribution group.

But the dist grp can’t be changed on the fly, so the Proj Manager’s email would be listed in both the TO and the CC (via the Dist Group).

Thoughts?

Bumping the thread as I’d also like to know. As far as I’ve seen, unless the adress is in a group, the email will just arrive once.

Most email systems are smart enough to not process the same email twice. So if you put your same email address in the cc field 10 times you’ll still only get one copy.

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