ESA can not bounce email after receive inexistence recipients email

[360rundll]

Hi all,

            As the title, what is the problem? Who can tell me? Any configuration must config?

BR.

[Libin Varghese]

Hi,

You would need to enable recipient validation for internal users using a LDAP server which the ESA can query to.

The query can be enabled on the listener you use to accept emails.

Please refer to the below article for reference

http://www.cisco.com/c/en/us/support/docs/security/email-security-appliance/118218-configure-esa-00.html

Regards
Libin Varghese

[Jernej Vodopivec]

Hi,

if you don't have LDAP you can still use SMTP call-ahead.

Be aware that invalid recipient counts for maximum number of invalid recipients for DHAP attack prevention.

[360rundll]

Hi Jernej,

         So, how to set SMTP call-ahead? Is it have a tutorial?

BR.

[dmccabej]

Hello,

You can view the instructions on how to enable SMTP call-ahead on the ESA in the ASyncOS User Guide (link below).

Validating Recipients Using an SMTP Server

Thanks!

-Dennis M.