Edit, i figured it out in the yaml file the quotes around some of the entries were stopping from being read. this is what i used , DISCOURSE_SMTP_ADDRESS: mail.the DISCOURSE_SMTP_PORT: 465 DISCOURSE_SMTP_USER_NAME: accounts-no-reply@ DISCOURSE_SMTP_PASSWORD: X DISCOURSE_SMTP_ENABLE_START_TLS: false DISCOURSE_SMTP_SSL: true DISCOURSE_SMTP_AUTHENTICATION: login DISCOURSE_SMTP_DOMAIN: t DISCOURSE_DEVELOPER_EMAILS: info@ DISCOURSE_NOTIFICATION_EMAIL: accounts-no-reply@ and default in the samples has quotes around alot of them like this DISCOURSE_SMTP_ADDRESS: ‘mail.’ the quotes were causing the domain, email and others to not be read for some reason. no matter what i do, i cannot get discourse to use a port for email other than 25, running on the standalone yml, ive even tried it in the yml, forcing it and no go kinda out of options at this point lol … not sure if this is a bug or not [SMTP OVERRIDE] Configured SMTP: {:address=>“mail.”, :port=>465, :domain=>“th”, :user_name=>“accounts-no-reply@m”, :password=>“”, :authentication=>:plain, :enable_starttls_auto=>false, :ssl=>true, :openssl_verify_mode=>“none”} Testing sending to y using mail.:25, username:accounts-no-reply@ with plain auth. ======================================== ERROR ======================================== Connection to port 25 failed. ====================================== SOLUTION ======================================= The most likely problem is that your server has outgoing SMTP traffic blocked. If you are using a service like Mailgun or Sendgrid, try using port 2525. i also had to force it not to use example.com as my domain as it kept forwarding me to it lol. very buggy XD

the mail is running on a clients website server i access via cpannel, pretty sure it uses sendmail on linux. really no reason i should need port 25 for smtp i think. thats if you’re hosting your own mail service. not smtp. no matter what i change it to in the yml, it always just tries to use port 25.

i was told if you try to outbound over port 25 your IP is blacklisted immediately i’m not sure is this standalone.yml part of an #advanced-setup

Yeah the standalone.yml is for if you have to use a non standard port and proxy on your webserver. For example I have it running on 127.0.0.1:3000 and nginx proxies it to 443 because I have 6 websites running on the same server so nginx can have many websites on the same IP address. discourse_docker/samples/standalone.yml at main · discourse/discourse_docker · GitHub Yeah running your own mail server on port 25 these days isn’t a great idea most email providers have blacklisted entire vps subnets.

Running a build on standalone.yml

Product Support

NateDhaliwal (Nate Dhaliwal) June 20, 2025, 2:16pm 2

Hi there, what SMTP provider are you using? Also, have you tried changing ports to 2525 or 587?

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Running a build on standalone.yml

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