reject mail with attachment and show a message instead
I'm new in term of linux environment and I really want to know if my problem have a solution or not.
So, I have the horde groupware installed, and the users could send email normally, but I want to know if I could prevent them of using the option to add attachment ? I change some files of the groupware in order to show the message ( please use filezilla to send attachment!) but if I configure the user on thunderbird, he could send the attachment.
so, in fact I chnage this from the client side, how can I do the same from the server side, so whatever the users use mail client, they will have the same behavior (alert them to use the Filezilla)