Have Receipt Processor ignore smime.p7s file on signed emails
We are rolling out digital certificates for our users as part of a security policy to sign all of our messages. This trips up the Receipt Processor because every sign message has an extra attachment called "smime.p7s" that contains the certificate information. Any time a user emails receipts, they get a message back saying that file could not be processed as a receipt image. This also sometimes causes their other, legitimate, receipt attachments to fail.
We would like the receipt processor to always ignore this attachment, "smime.p7s", or really any file with the "p7s" extension. This change would benefit any company that uses digital signatures to verify the sender of a message.