You have a great product. Thanks for creating the forum platform.
For my two forums I would like to disable "post by email". The subscribe by email is fine for our forum and it may remain there. If it is not possible to keep one of them active, then we would prefer to deactivate both of these.
You have to edit two macros:
1- send_subscription_email in order to remove the reply email address, so that the subscriber won't be able to reply the message, he will receive a "no-reply" address at the from field instead: