Where did you install Firefox from? Help Mozilla uncover 3rd party websites that offer problematic Firefox installation by taking part in our campaign. There will be swag, and you'll be featured in our blog if you manage to report at least 10 valid reports!

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

This thread was archived. Please ask a new question if you need help.

Can,t send emails to Gmail addresses due to SMP setting??

  • 1 reply
  • 0 have this problem
  • 1 view
  • Last reply by david

lilyflds
lilyflds
more options

I can't send any emails via THunderbird to any Gmail address...is this a Thunderbird settings issue or do I need to sort it with my ISP?

A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: 

 lilyflds@gmail.com
   host gmail-smtp-in.l.google.com [142.251.111.26]
   SMTP error from remote mail server after pipelined end of data:
   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 [southernphone.com.au]
   550-5.7.26 did not pass with ip: [54.160.229.207]. 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. n7-20020a05622a040700b003e4e39b3567si577659qtx.593 - gsmtp
I can't send any emails via THunderbird to any Gmail address...is this a Thunderbird settings issue or do I need to sort it with my ISP? A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: lilyflds@gmail.com host gmail-smtp-in.l.google.com [142.251.111.26] SMTP error from remote mail server after pipelined end of data: 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 [southernphone.com.au] 550-5.7.26 did not pass with ip: [54.160.229.207]. 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. n7-20020a05622a040700b003e4e39b3567si577659qtx.593 - gsmtp

All Replies (1)

david
david
  • Top 10 Contributor
more options

This is a security error that only your email provider can fix. We have seen several similar posts in past week, as Google seems to have tightened security on their email.