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Can't send to gmail accounts

  • 4 respostas
  • 3 have this problem
  • 56 views
  • Last reply by david

gerry18
gerry18
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Suddenly, neither my wife or I can send emails to anyone with a gmail.com address. I even tried sending one to my own gmail account and it failed. We're both using the most current version of Windows and version 102.11.2 of Thunderbird. Here is failure message.

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 [montanapens.com] did not 550-5.7.26 pass with ip:
   [146.20.161.78]. 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.
   i21-20020a05620a151500b0075c984c68d1si3680713qkk.545 - gsmtp
Suddenly, neither my wife or I can send emails to anyone with a gmail.com address. I even tried sending one to my own gmail account and it failed. We're both using the most current version of Windows and version 102.11.2 of Thunderbird. Here is failure message. 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 [montanapens.com] did not 550-5.7.26 pass with ip: [146.20.161.78]. 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. i21-20020a05620a151500b0075c984c68d1si3680713qkk.545 - gsmtp

All Replies (4)

david
david
  • Top 10 Contributor
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Please share this with your email provider. Google has tightened security on email and many personal domains are not fully configured for security. Your email provider can make the appropriate DKIM and SPF changes.

gerry18
gerry18 Question owner
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Thanks, I will call them tomorrow.

cheistek
cheistek
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I got a similar message : [edited] @gmail.com 

   host gmail-smtp-in.l.google.com [142.251.163.26]
   SMTP error from remote mail server after end of data:
   550-5.7.26 This mail has been blocked because the sender is unauthenticated.
   550-5.7.26 Gmail requires all senders to authenticate with either SPF or DKIM.
   550-5.7.26
   550-5.7.26  Authentication results:
   550-5.7.26  DKIM = did not pass
   550-5.7.26  SPF [sympatico.ca] with ip: [67.215.8.22] = did not pass
   550-5.7.26
   550-5.7.26  To mitigate this issue, please visit Gmail's authentication guide
   550-5.7.26 for instructions on setting up authentication:
   550 5.7.26  https://support.google.com/mail/answer/81126#authentication h4-20020a05620a10a400b0076cb1c1cd67si8559603qkk.655 - gsmtp

As suggested above, I contacted Sympatico and they said the problem was with Thunderbird. Now what?

James modificouno o

david
david
  • Top 10 Contributor
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Unfortunate that some email provider tech support personnel deny problems. You might try this site at https://www.alitajran.com/check-spf-dkim-dmarc/ to see if their testing can help prove the problem - but I have not used the service myself.