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Emails to gmail addresses suddenly return undeliverable

  • 5 respuestas
  • 8 tienen este problema
  • 2 visitas
  • Última respuesta de david

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Emails to gmail addresses return undeliverable. I receive this message:

Action: failed Status: 5.7.26 Remote-MTA: dns; gmail-smtp-in.l.google.com Diagnostic-Code: smtp; 550-5.7.26 This mail is unauthenticated, which poses a

   security risk to the 550-5.7.26 sender and Gmail users, and has been
   blocked. The sender must 550-5.7.26 authenticate with at least one of SPF
   or DKIM. For this message, 550-5.7.26 DKIM checks did not pass and SPF
   check for [my email address] 550-5.7.26 did not pass with ip:
   [23.83.218.247]. The sender should visit 550-5.7.26
   https://support.google.com/mail/answer/81126#authentication for 550 5.7.26
   instructions on setting up authentication.
   d2-20020a170902aa8200b001aaf5dcd774si19262143plr.173 - gsmtp

Any assistance would be appreciated. Thanking you.

Emails to gmail addresses return undeliverable. I receive this message: Action: failed Status: 5.7.26 Remote-MTA: dns; gmail-smtp-in.l.google.com Diagnostic-Code: smtp; 550-5.7.26 This mail is unauthenticated, which poses a security risk to the 550-5.7.26 sender and Gmail users, and has been blocked. The sender must 550-5.7.26 authenticate with at least one of SPF or DKIM. For this message, 550-5.7.26 DKIM checks did not pass and SPF check for [my email address] 550-5.7.26 did not pass with ip: [23.83.218.247]. The sender should visit 550-5.7.26 https://support.google.com/mail/answer/81126#authentication for 550 5.7.26 instructions on setting up authentication. d2-20020a170902aa8200b001aaf5dcd774si19262143plr.173 - gsmtp Any assistance would be appreciated. Thanking you.

Todas las respuestas (5)

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The information is that your email domain cannot be authenticated. You may wish to check with your email provider to fix this. The references to DKIM and SPF are server configuration settings, in no way related to Thunderbird.

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Thanks for your reply. Why would it be that its only gmail addresses that won't accept my emails? Regards, Brendan.

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It may be that Gmail has more security checks.

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Thanks for your reply David. Last question: why did this happen randomly? I used to be able to send emails to any email address? Regards, Brendan.

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We see several posts on changing security among email providers. I agree this can be confusing, but it's a sign of continuing security concerns.