Why was the email I tried to send marked as spam?

Anti-spam detection methods look at several factors and create a “spam score” for each message. When a spam score is high enough, the message will be marked as spam.


Sometimes a message will have a high spam score even when the message is not spam.


Here are some simple ways to avoid common mistakes which can raise the spam score for your message.


  • Avoid strange use of capitalization, symbols, and punctuation.
    • Don’t use ALL CAPS or aLtErNaTe capitalization for effect.
    • Don’t use symbols like @ or ! as substitutes for letters in a word.
    • Emails with multiple exclamation points or question marks can look suspicious.
  • Make sure your emails are at least one full sentence.
    • Don’t send an email that only includes an embedded image or link
    • Spam messages are often very short, sentence fragments, or only a few words.
  • Your subject line should be related to the body of your email message.
    • Spammers often try to lure you in with a misleading subject line.
  • Limit the use of common spam phrases.
    • Words like “free” and “diet” and “pharmaceuticals” are often used in spam messages.
  • Avoid deceptive and malicious links in your message as well as an excessive amount of links.
  • Too many attachments can make your message appear suspect.
  • Avoid using a reply-to address that goes to a different domain than your sender address.



If your message has been marked as spam incorrectly, look at the list above, make any necessary changes, and try sending again.

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