Start with one real delivery problem
A quotation that reaches spam can delay a sale. An invoice that disappears can create unnecessary follow-up work. Before changing providers or repeatedly resending, collect one example: the sender, recipient, sending time, subject and any error message. Ask whether the message was rejected, arrived in spam or cannot be found. These are different outcomes.
Keep a copy of the original message and its full headers if available. Share diagnostic information privately with your provider, rather than posting customer correspondence online. A specific example is much more useful than a general report that email is not working.
Identify every system that sends for your domain
Your team’s mail app may be only one sender. A website form, invoicing platform and newsletter tool can each send independently. Make a short inventory and test each route separately. A successful test from your own mailbox does not prove the invoice platform is configured correctly.
Ask your provider to check authentication for each route. SPF identifies authorised sending infrastructure, DKIM adds a domain signature, and DMARC checks alignment with the visible sender domain. Google recommends configuring all three. Have existing senders reviewed before tightening a DMARC policy so legitimate messages are not unexpectedly affected.
Look beyond the words in the message
Authentication is important, but it is not a guaranteed inbox pass. Google’s guidance also covers sending infrastructure, reputation and recipient complaints. Your hosting provider may need to investigate issues with a shared sending IP. Changing a subject line alone will not repair those problems.
For your own review, use an accurate sender name and a subject that describes the actual message. Check that contact details, links and attachments are expected by the recipient. Avoid presenting a new message as an existing reply. If a PDF is unusually large, ask whether a smaller version or an agreed document-sharing method would be more practical.
Run a controlled test
Send a normal, short business message through the affected system to a test recipient who has agreed to help. Record the time and result, then change one relevant setting at a time with your provider. This makes it easier to tell whether a fix worked.
For ongoing newsletters, use a permission-based list and an easy way to opt out. Remove addresses that repeatedly fail. Keep routine customer correspondence and bulk campaigns operationally distinct, with appropriate tools and clear ownership.
Know what to send your provider
Prepare the domain, sending application, affected recipient provider, approximate starting date and one recent example. Mention any recent DNS, hosting or invoicing-platform changes. Do not send your mailbox password in an ordinary support message.
OnHypp can review the agreed hosting and domain configuration scope and help identify the next action. Some issues need the sending platform or receiving organisation to investigate. The useful goal is a documented diagnosis and a measurable improvement, rather than a promise that every message will always reach the inbox.