// how to fix

How to fix email problems

Your test or scan found a problem? Find the matching guide below: what it means, why it matters, and how to fix it step by step.

DNS 33 DMARC 28 SPF 28 DKIM 26 Reputation 24 Bounce 16 Security 16 Blacklist 13 Gmail 13 Content 12 Mailing list 11 Spam score 10 Headers 9 Reverse DNS 7 Mail server 4 Microsoft 365 4 MX 4 Outlook 4 TLS 2 Apple 1 BIMI 1 E-commerce 1 Google Workspace 1 WordPress 1 Yahoo 1 Zoho 1

12 guides · tag Content

Problem	In short	Tags
Links that hurt deliverability	URL shorteners, link text that shows one address but points to another, and links to blacklisted domains are classic spam signs. Use plain links to your own domain.	Content Blacklist Spam score	Fix it
Image-only emails and missing plain-text version	An email that is one big image, or that has no plain-text version, looks like spam to filters. Use real text, a few images, and send both HTML and plain text.	Content Spam score	Fix it
Attachments blocked or flagged as dangerous	Some file types are refused outright, large files bounce, and unexpected attachments raise spam scores. Send safe formats, keep them small, or share a link instead.	Content Security	Fix it
Cold emailing without landing in spam	Prospecting emails are judged harshly by Gmail and Outlook. Protect your main domain, send slowly, write like a person and make opting out easy.	Reputation Content Spam score	Fix it
Choose a good sender name and From address	The sender name and address are the first things people see. Pick ones that are clear, stable and on your own domain, and readers trust and open your emails.	Content Reputation Headers	Fix it
Why "no-reply" addresses hurt your emails	Sending from noreply@ tells readers you do not want to hear from them. It costs you replies, trust and sometimes inbox placement. Use a real address instead.	Content Reputation	Fix it
Spammy subject lines and words that trigger filters	Shouting subjects, fake urgency and pushy money words make filters and readers suspicious. Write calm, honest subjects that match the content.	Content Spam score	Fix it
Your emails land in Gmail's Promotions tab	The Promotions tab is not spam: Gmail is sorting your marketing emails. Learn when it is normal, and what helps personal and transactional emails stay in Primary.	Gmail Content	Fix it
Email too big: Gmail clips messages over 102 KB	When the HTML of an email is larger than about 102 KB, Gmail cuts it and shows "[Message clipped]". Your unsubscribe link and footer can disappear.	Gmail Content	Fix it
Garbled characters: fix encoding and charset problems (UTF-8)	Accents turning into "Ã©" or question marks mean the email does not declare its text encoding correctly. Use UTF-8 everywhere and declare it.	Content Headers	Fix it
Legal footer: unsubscribe link and postal address in marketing emails	Marketing emails need a clear way to unsubscribe and information about who you are. Here are the basics of CAN-SPAM and GDPR, and a simple footer to copy.	Content Mailing list	Fix it
Use a custom tracking domain for links in your emails	Newsletter tools rewrite your links through a shared tracking domain. If that domain gets a bad name, your emails suffer. Use your own instead.	Content Reputation Blacklist DNS	Fix it

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