4- Anti-spam

https://www.juniper.net/documentation/en_US/junos/topics/concept/utm-antispam-filter-overview.html

Antispam filtering allows you to use both a third-party server-based spam block list (SBL) and to optionally create your own local whitelists (benign) and blacklists (malicious) for filtering against e-mail messages.

Action to Block:

• Blocking spam at the connection level ( sender SMTP server  IP@ )

• Blocking spam at the e-mail level ( email send address is block )

1- create or used default anti-spam profile

2- create an utm-policy + anti-spam 

3- Add to security Policy ( from Zone to Zone ) the utm-policy