A quiet inbox can hide a delivery problem. If a customer says they never received your quote, it is worth checking the journey before assuming they lost interest. Rewriting the subject line alone may not address the cause.

Start with an actual example

Choose a recent message that went missing. Note the sender, recipient, approximate time, and which application sent it. Ask whether it landed in spam, bounced, or never appeared. Those are different symptoms. Keep any bounce message intact rather than forwarding only the error number. Compare a normal staff email with a website notification: they may use different sending services.

Check the business behind the address

Make a list of everything that sends using your domain: your mailbox provider, invoicing tool, booking system, website, and newsletter platform. An old tool can be overlooked when a domain changes. Email authentication helps receivers check whether a sender is authorised; Google recommends SPF, DKIM, and DMARC. Authentication is a foundation, not a promise of inbox placement.

Make the next test useful

Avoid changing several settings at once. Have the configuration reviewed, record the change, and compare results using the same message type. Test replies as well as new messages. If the issue affects only one organisation, that recipient’s administrator may need to investigate. Keep customer follow-up separate: a phone call can confirm receipt while the technical work continues.

MAKE IT ACTIONABLE

Your next steps

  • Save one missing-message example and any bounce notice.
  • List all systems that send as your business.
  • Confirm the customer’s address using a known contact method.
  • Ask for a review before changing domain records.

Official reference

Google: Email sender guidelines

Technical guidance checked September 29, 2026. Product features and requirements can change. The business checklists above are practical suggestions from Cyber Bounds.

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