A malformed message is a pause

Answer A malformed message is a pause. RFC 7103 is advice for the safe handling of messages that are not well formed. The advice is for implementers who meet broken mail in the wild. The lesson for a buyer is simpler. When a message is broken, stop. Look at the bytes you actually have. Do not let a seller repair it into a tidier letter and then talk as if the tidier letter is the one they signed and the one the reader got.

The note that started this: RFC 7103, Advice for Safe Handling of Malformed Messages, RFC 7103.

Broken shows up on solo ads as a creative that looked fine in a browser and arrived as a hash of missing parts, a subject that turned into question marks, or a link that a relay rewrote into something else. The temptation is to let the platform smooth it over and keep the schedule. If you are vetting safe solo ads sellers, the schedule is the thing that can wait. The broken message is the exhibit.

This note will not hand you a list of edits. Edits are how a signed message becomes a different message, and a different message can fail authentication for reasons that look like a mystery. The safe buyer move is to keep the original, keep the received copy, and ask the operator what their software changed. If they cannot say, they do not control the path they are selling.

What should you do with a malformed email?

Pause. RFC 7103 is advice for handling malformed messages safely. A broken message is a reason to stop and look at what actually arrived. It is not a cue to invent a cleaner message and call it the same send.

Look means a human opens the raw message, or a careful tool shows it without repairing it on the way in. You want the defect visible. A preview that auto-corrects has hidden the evidence. Save the file. Note the time. Note which system produced it. Then decide whether the send should happen. A decision made after the mail is already in a million mailboxes is a postmortem. A pause is cheaper.

The specification exists because well-meaning software has historically tried to be helpful and has made the mess worse, or has opened a hole while trying to display the mess. Helpful is not the same as faithful. Faithful, for your order, means the creative you approved is the creative that left, and the creative that left is the creative a test mailbox received.

• The broken copy is saved before anyone rewrites it.
• The approved creative is compared with a received test.
• The seller names any change their platform made.
• The send waits until the comparison is boring.

Can a platform safely rewrite a broken message?

Sometimes a platform has to refuse it. Rewriting headers or body so the message looks valid can produce a different message from the one that was signed. Ask what their system does. Do not accept the word fixed without a before and an after.

Refuse is a legitimate outcome. A message that is not well formed can be dropped, bounced, or held. Those are visible. A silent rewrite is not visible unless you diff the before and the after. Ask for the diff on a test. If the only answer is that customers never see a problem, ask how they would know. Customers who see a problem often just complain, or just leave, and the dashboard still says delivered.

DKIM is the practical reason to be stubborn. A signature covers what it covers. Change a covered part and the signature no longer matches. A seller who repairs a header and then celebrates a fresh signature has signed the repair, not the original. That can be honest if they tell you. It is a different send. Label it as a different send, with a new test, before you pay for the drop.

Does cleaning a malformed solo ad prove the list is fine?

No. A syntax problem and a list problem are different. A pause lets you see which one you have. A file that only works after invisible repairs is a file you have not actually seen.

Syntax is the shape of the message. The list is the people. You can have a perfect list and a broken creative, or a beautiful creative and a file of strangers. Cleaning the creative does not speak to the file. Sellers who rush from a display bug to a claim that the traffic is safe have changed the subject. Bring them back. The bug is a pause. The file is still a question. Answer them one at a time.

RFC 7103 is a caution to people who write mail software. Borrow the caution. A malformed message is a pause. The letter you meant to send can go when it is the letter you can show.