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Common email problems, explained

Every problem SenderCheck can find, in plain English: what’s wrong, what it means for your business, and how to fix it step by step. The technical name sits under each one for whoever needs it.

Your list of approved senders

  • You have two lists of approved senders, which cancels both out

    Only one list is allowed. With two, receivers ignore both, so every email you send fails this check and is more likely to land in spam or be rejected.

    More than one SPF record published

    Fix first

  • Some services on your list of approved senders are being ignored

    A service was added after the list's closing entry, and receivers stop reading there. Emails sent through that service aren't approved and may land in spam or be rejected.

    SPF record has mechanisms after the all term

    Worth fixing

  • Your list of approved senders doesn't turn anyone away

    It says who may send as you but takes no position on everyone else, so receivers treat it much like having no list. A one-word change at the end makes it count.

    SPF record ends with ?all

    Worth fixing

  • Your settings approve anyone in the world to send email as you

    Your list of approved senders ends with a setting that approves every server on the internet. Scammers can send email in your name and it will pass this check. That is worse than having no list at all.

    SPF record ends with +all

    Fix first

  • You have no list of approved senders

    Receivers can't check that your emails come from services you actually use, so invoices and replies are more likely to be treated with suspicion. Gmail, Yahoo and Outlook expect businesses to have one.

    No SPF record found

    Fix first

  • Your list of approved senders has a typo in it

    Part of the list isn't written correctly. Some receivers ignore the whole list when that happens, so the same email can pass at one company and fail at another.

    SPF record contains a syntax error

    Fix first

  • Your list of approved senders is over its limit

    Receivers stop reading a list that points to too many services, and then treat the whole list as broken. That affects every email you send, not just the ones from the last services listed.

    SPF record exceeds the 10 DNS lookup limit

    Fix first

Your email's digital seal

  • We couldn't find your email's digital seal where we usually look

    It may be set up under a name we can't see, which is common. If it truly is missing, forwarded emails are more likely to fail checks. Your email provider can tell you which is the case.

    No DKIM key found at the selectors we checked

    Small improvement

  • Your email's digital seal is damaged and can't be read

    The setting was likely cut short or had spaces added when it was pasted. Every email sealed with it fails the check, and nothing warns you because your provider thinks it's working.

    DKIM record is malformed

    Fix first

  • Your email's digital seal is too weak to trust

    It uses an outdated, short code that can be cracked, which would let scammers make fake emails look sealed by you. Some receivers already refuse it. Your email provider can issue a stronger one.

    DKIM key is shorter than 1024 bits

    Fix first

Your instructions for fake emails

  • Your reports are going somewhere that hasn't agreed to accept them

    Your reports are addressed to another domain that hasn't confirmed it accepts them, so receivers quietly don't send them. The fix is made on that other domain; if it's a reporting service, ask them.

    External reporting address is not authorised

    Worth fixing

  • You're not getting reports on who sends email as you

    Without reports you can't see which services send in your name, or know when it's safe to start blocking fakes. Adding an address for reports doesn't change how your email is delivered.

    DMARC record requests no aggregate reports

    Worth fixing

  • Fake emails pretending to be you are still delivered

    Your instructions for fake emails are set to watch only. That's the right first step, but fakes in your name still get through. Once your real emails are confirmed to pass, you can tell receivers to block fakes.

    DMARC policy is set to none

    Worth fixing

  • Nothing tells receivers to block fake emails pretending to be you

    Without instructions for fake emails, scammers can email your customers in your name with nothing from you standing in the way, and you get no reports showing who is sending as you.

    No DMARC record found

    Fix first

  • Fakes from addresses like billing.yourbusiness.com aren't blocked

    Your main address is protected, but variations of it have weaker instructions. Scammers can invent one (it doesn't need to exist) and use it to send fake emails in your name.

    Subdomain policy is weaker than the domain policy

    Worth fixing

  • Your instructions for fake emails have a typo

    Receivers can't read them, so they may throw them out entirely. Fake emails in your name then aren't blocked, even though your settings look like they should be.

    DMARC record contains a syntax error

    Fix first

  • Your instructions for fake emails are being ignored

    You have two sets of instructions where only one is allowed, so receivers ignore both. Any protection you set up is effectively switched off, and your reports stop arriving.

    More than one DMARC record published

    Fix first

Your mailbox settings

  • Your domain has no email settings at all

    It can't receive email, and nothing stops scammers sending email in its name. If you use it for email, it isn't set up yet; if you don't, three quick settings lock it down.

    No email configuration of any kind was found

    Worth fixing

  • Your mailbox settings point to an address that doesn't exist

    Senders trying to reach you can't connect to that address. Emails to you may be delayed, or, if there's no working backup, not arrive at all.

    An MX host does not resolve to an address

    Fix first

  • Some emails sent to you may not arrive

    Your mailbox settings point to a shortcut name instead of the real address. Many senders follow it, but some refuse, so a few customers' emails may never reach you and you won't know.

    An MX record points at an alias

    Worth fixing

  • Your business can't receive email at this domain

    There are no mailbox settings, so emails sent to you, like customer inquiries and replies to your quotes, bounce back. If you don't use this domain for email, you can say so instead.

    No MX records found

    Fix first

  • Scammers could send email from this unused domain

    This domain doesn't seem to send email, but nothing says so. Scammers favor unused domains because nobody is watching. Three settings lock it down for good and need no upkeep.

    Non-sending domain is not protected against forgery

    Worth fixing

Encrypted delivery

Your logo in the inbox

  • Your logo won't show until fake emails are blocked

    Inboxes only show your logo once your instructions for fake emails tell receivers to block them. Switch that on only after confirming your own emails pass, or real ones could be blocked.

    BIMI record published without DMARC enforcement

    Worth fixing