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Need SMTP help macOS 11.4 and Thunderbird 78.11

  • 4 replies
  • 2 have this problem
  • 8 views
  • Last reply by sfhowes

egeary
egeary
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I have new iMac running macOS 11.4 (Big Sur) and I'm trying to set-up Thunderbird 78.11 SMTP server. Using Optimum (optonline.net) cable service. I can't find setting that work!

I have new iMac running macOS 11.4 (Big Sur) and I'm trying to set-up Thunderbird 78.11 SMTP server. Using Optimum (optonline.net) cable service. I can't find setting that work!

All Replies (4)

sfhowes
sfhowes
  • Top 10 Contributor
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Have you tried mail.optonline.net on 465, SSL/TLS, authentication = normal password, User Name = part of email address before @?

https://faq.optimum.net/node/7327

solutions25
solutions25
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Tried that approach (465) to no avail. Tried with authentication and normal password and no authentication. Tried SSL/TLS, STARTTLS and NONE. Tried no authentication and normal password. I got nothing.

egeary
egeary Question owner
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I think I've tried every combination of setting s and I know all my details are entered correctly. I've spoken with my ISP who is also stumped. I'm figuring this is an issue between Thunderbird 78.x and macOS 11.x (Big Sur) I will continue to seek answers from all parties.

sfhowes
sfhowes
  • Top 10 Contributor
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There's no point in trying random settings. Use the ones recommended by the mail provider.

What is the proxy setting in Preferences/General/Network & Disk Space/Connection? Some Mac users have to set 'No proxy'.

What is the antivirus/VPN configuration?