Hello, first post here. How would I block sending to specific email addresses using Sendmail? One of my customers would like to be able to stop users from sending to specific email addresses. We have blocked reception of these addresses via Spam Control, but now they would like to stop the users from sending. Any help would be appreciated. (Using Suse Enterprise v10.)

Hello,
I build a virtual machine to answer you because I don't use anymore sendmail I prefer postfix.

The best and easiest way, is to enter the routine below into "/etc/mail/access"
mailadr2avoid ERROR:"No mail please !"

Once you have modified that file, run "make".

if don't have make installed, you can directly execute "makemap hash /etc/mail/access.db < /etc/mail/access"

after that "service sendmail restart"

To test it, inside a console type "telnet host 25"
helo test.com
mail from:mailadr2avoid

you should get an error message