On 22/01/16 08:47, Peter Funk wrote:
> I would like our exim mail server to block any incoming emails
> which only have one or more HTML attachment(s) and don't
> contain at least one plain text attachment.
Have a look into the ACL configurable via al_smtp_mime.
Use that to count HTML parts and plaintext parts.
Then in data ACL, evaluate and deny where appropriate.
http://exim.org/exim-html-current/doc/html/spec_html/ch-content_scanning_at_acl_time.html#SECTscanmimepart
--
Cheers,
Jeremy