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Can't send messages to gmail users

  • 2 (ردّان اثنان)
  • 0 have this problem
  • 1 view
  • آخر ردّ كتبه david

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My wife and I run Linux Mint 21.1 on identical PCs. Our internet provider is zen.co.uk. We both have TB 102.15.0 and Italian e-mail addresses with tiscali.it.

For some time now every message she sends to somebody with a gmail address bounces with this error message: "host gmail-smtp-in.l.google.com [64.233.166.27] 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 [tiscali.it] did not pass 550-5.7.26 with ip: [212.23.1.22]. 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. bg25-20020a05600c3c9900b003fa96fd77e9si4408746wmb.232 - gsmtp"

Her server settings for the Tiscali.it account are POP Mail Server; port 110 SSL/TLS password transmitted insecurely empty deleted folder on exit

I don't have this problem. My settings are IMAP Mail Server; port 993 SSL/TLS and encrypted password deletion to Trashcan

Is the solution to convert her Tiscali account settings to IMAP? If so, how should I do that?

My wife and I run Linux Mint 21.1 on identical PCs. Our internet provider is zen.co.uk. We both have TB 102.15.0 and Italian e-mail addresses with tiscali.it. For some time now every message she sends to somebody with a gmail address bounces with this error message: "host gmail-smtp-in.l.google.com [64.233.166.27] 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 [tiscali.it] did not pass 550-5.7.26 with ip: [212.23.1.22]. 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. bg25-20020a05600c3c9900b003fa96fd77e9si4408746wmb.232 - gsmtp" Her server settings for the Tiscali.it account are POP Mail Server; port 110 SSL/TLS password transmitted insecurely empty deleted folder on exit I don't have this problem. My settings are IMAP Mail Server; port 993 SSL/TLS and encrypted password deletion to Trashcan Is the solution to convert her Tiscali account settings to IMAP? If so, how should I do that?

All Replies (2)

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The issue is that the email provider's email server needs security updates. This has nothing to do with POP or IMAP. These messages need to be shared with the email provider to have corrected. They will know what has to be done because the DKIM and SPF issues mentioned in messages are known concerns. This is happening because many email hosts (such as Gmail) are now putting more stringent security controls in place. Again, there is nothing to do in Thunderbird or the account; this is a problem that must be fixed on the server.

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As an aside, I suggest she increase security of her account and use encrypted password. That is a separate issue from the problem being reported. It's just safer.