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cannot reply or send messages to gmail accounts - error message 550-5.7.26 pops up

  • 1 reply
  • 1 has this problem
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  • Last reply by Matt

rodriguez.realestate
rodriguez.realestate
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I cannot reply to or write a message to any Gmail accounts. Everything else is working fine. This may of happened shortly after I tried to create a junk and better filter my spam folder. Following other advice posts, I've checked and smtp is set to "normal password". Any help would be greatly appreciated, Thank you.

This same error message keeps popping up; SMTP error from remote mail server after end of data: 

   550-5.7.26 This message does not have authentication information or fails to
   550-5.7.26 pass authentication checks. To best protect our users from spam, the
   550-5.7.26 message has been blocked. Please visit
   550-5.7.26  https://support.google.com/mail/answer/81126#authentication for more
   550 5.7.26 information. h5si126304jaj.90 - gsmtp
I cannot reply to or write a message to any Gmail accounts. Everything else is working fine. This may of happened shortly after I tried to create a junk and better filter my spam folder. Following other advice posts, I've checked and smtp is set to "normal password". Any help would be greatly appreciated, Thank you. This same error message keeps popping up; SMTP error from remote mail server after end of data: 550-5.7.26 This message does not have authentication information or fails to 550-5.7.26 pass authentication checks. To best protect our users from spam, the 550-5.7.26 message has been blocked. Please visit 550-5.7.26 https://support.google.com/mail/answer/81126#authentication for more 550 5.7.26 information. h5si126304jaj.90 - gsmtp

All Replies (1)

Matt
Matt
  • Moderator
  • Top 10 Contributor
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I have no idea what domain you are supposedly reply from, but I would guess it to be a bargain basement self hosting arrangement without the requisite things like DMARK, DKIM and reverse DNS entries configured.

These things are all discussed in the link you posted with your request and need to be addressed by the domain owner or mail administrator. They are unrelated to Thunderbird and relate to the initial configuration of the domain and it's mail server.