An administrator notices that incoming emails with certain attachments do not get delivered to all...

By modifying the mail policies, specifically the recipient matching criteria, you can ensure that email recipients do not match multiple policies simultaneously. When recipients in the email message belong to different domains (e.g., cisco.com and test.com), it can result in multiple policies being triggered simultaneously, leading to inconsistent delivery of emails with attachments.

DLP is for outgoing mail only and not relevant to incoming mail.