Blocking Large E-mail Blasts

EV42TMAN

Hello Everyone,

I have an interesting problem, in Exchange 2013 is there a way to create a rule to block a user from sending an e-mail to a large group of people who are outside of the organization. A user sends a newsletter out of outlook instead of using mailchimp. I just want to block her from sending an e-mail to 300+ people. If you have any ideas let me know. Thank you in advance.

Ecio

I'm not (yet) managing Exchange 2013 so I've never tried them but:

You should be able to limit the number of recipients on a single message (even at the mailbox level) if he's sending them with a single message:
Message Size Limits: Exchange 2013 Help
or use some kind of policy to limit the number of messages per minute, or recipients per minute
Message Throttling: Exchange 2013 Help
EWS throttling in Exchange
if he's using a mailmerge send (so each message is sent independently)

EV42TMAN

Thank you for the links. I tried to created a transport rule so when she would try to send an e-mail blast it would give her a pop saying something like "user name....this is why we pay for mailchimp" or something more professional that gets the point across. Unfortunately the transport rules from the ECP doesn't allow you to filter it by number of recipients and the filtering options that it does support would be too restrictive. Oh how I hate navigating company politics...