Email troubleshooter
Tell us what's going wrong. The troubleshooter reads your bounce message, checks your domain's live email records, and puts the likely causes in order, with the fix for each one and a report you can send to IT.
How the troubleshooter decides
It combines three kinds of evidence and labels each result, so you know how sure it is:
- Found: confirmed by a live DNS lookup of your domain, or by the error code in your bounce message.
- Possible cause: a common cause of this problem that can't be tested from a browser, such as a hacked account or a daily sending limit.
- Worth checking: something that may or may not apply, such as a DKIM key we couldn't find on the usual selector names.
Results are ranked by how likely they are to explain your problem. A confirmed "no such domain" or a failing SPF record always comes before general advice.
What it can't check
- Your sending IP's reputation and blocklist status. Look for a blocklist name in the bounce message.
- Whether a message reached the inbox or spam. Only the receiving provider knows that.
- Your account settings, passwords or billing.
- DKIM keys with unusual selector names. Use the DNS checker with your selector to be sure.
Other tools for one job
- Bounce message decoder: just explain a bounce.
- MX, SPF, DKIM and DMARC checker: the full DNS report for a domain.
- Email header analyzer: check where a message really came from.
- SMTP error code library and email server settings.
Questions people ask
- Why are my emails not being delivered?
- The most common reasons are a wrong address, missing SPF, DKIM or DMARC on the sending domain, a blocklisted sending server, and sending too much too fast. The troubleshooter checks the ones that can be tested and ranks the rest.
- Is the troubleshooter free?
- Yes. No sign-up, and it runs in your browser.
- Can I send the result to my IT person?
- Yes. Use the Copy button under the report. It lists what was checked, what was found and the likely causes in order.