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I'm trying to figure out how to prevent accidental leak of clients emails addresses when employee pastes them to CC instead of BCC.

Is it a way to restrict sending cc mails to addresses from whitelist? (@companydomain)

Any other solutions eliminating this scenario are more than welcome ;-)


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1. What do you mean accidental leak of clients emails addresses? Where would these email addresses be leaking to? 2. You're trying to fix a human problem with a technical solution, which is almost entirely impossible. – joeqwerty Apr 23 '14 at 22:14
accidental leak = sb pastes clients email to cc instead of bcc. Leakage to the rest of clients - its serious privacy concern. Impossible? My quick idea was to allow sending 'cc emails' in internal communication only ie. allow only for domains owned by my company. It doesn't look like rocket science to me, I just didn't find any decent information how to achieve this. :-) – Peter Nawrot Apr 23 '14 at 22:41

There are add-ins that forces you to confirm external recipients. These add-ins can show you if the recipients are in CC or in BCC, and thus provide an extra layer of security.

I think more info is available here:

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