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cannot send mail since last Thunderbird update

  • 2 replies
  • 1 has this problem
  • 12 views
  • Last reply by Wayne Mery

canfordv
canfordv
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Running Win 10 Pro v 1909. ESET antivirus 13.2.18.0 Thunderbird version 78.3.1 Windows firewall ISP is inter.net Canada (ca.inter.net) All settings in my Thunderbird match what inter.net Canada says they should be With outgoing connection security set to STARTTLS, error message is "peer using unsupported version of security protocol. Correct SMTP configuration" If I change outgoing connection security back to none, then I get the error message on sending mail "mail server response 5545.7.1 <userID of recipient> recipient address rejected. Check recipient address" where I know it to be valid.

I can send from this email account using my iPad!

Running Win 10 Pro v 1909. ESET antivirus 13.2.18.0 Thunderbird version 78.3.1 Windows firewall ISP is inter.net Canada (ca.inter.net) All settings in my Thunderbird match what inter.net Canada says they should be With outgoing connection security set to STARTTLS, error message is "peer using unsupported version of security protocol. Correct SMTP configuration" If I change outgoing connection security back to none, then I get the error message on sending mail "mail server response 5545.7.1 <userID of recipient> recipient address rejected. Check recipient address" where I know it to be valid. I can send from this email account using my iPad!
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All Replies (2)

sfhowes
sfhowes
  • Top 10 Contributor
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See https://support.mozilla.org/en-US/questions/1295861

You're better off adjusting the pref. to use the lower-version TLS than setting security to none.

If you're up to it, contact ca.inter.net to complain that their website doesn't even support https, let alone their mail server security being out of date.

Wayne Mery
Wayne Mery
  • Moderator
  • Top 10 Contributor
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see https://support.mozilla.org/en-US/kb/thunderbird-78-faq