Redmine

Our configuration is super simple and uses the local SMTP server on the same box to receive email, so our example wouldn't be of much help.

Looking at the configuration.yml file I see several examples there which appear similar to yours, but many of the values are quoted. I'm not familiar enough with YML conf files to note whether quotes are required or if whitespace matters, but I tend to assume it is.

Here is the example that I see in the file which may apply to your situation:

production:
  email_delivery:
    delivery_method: :smtp
    smtp_settings:
      tls: true
      address: "smtp.gmail.com" 
      port: 587
      domain: "smtp.gmail.com" # 'your.domain.com' for GoogleApps
      authentication: :plain
      user_name: "your_email@gmail.com" 
      password: "your_password" 

Thanks, Deoren.

You're welcome, did you figure it out?

I was experimenting in DigitalOcean's droplet. I shut down that droplet.

I think it started working when I changed delivery_method: from :async_smtp to :smtp

Glad to hear it, and thanks for noting the specific fix.