Redmine

Can you describe the problem in more detail?
What would you like to achieve? Do you want redmine to send emails, or would you like it to receive and process mails?

My configuration.yml is:

production:
  email_delivery:
    delivery_method: :smtp
    smtp_settings:
      tls: true
      enable_starttls_auto: true
      address: "smtp.gmail.com" 
      port: 587
      domain: "mars3142.org" # 'your.domain.com' for GoogleApps
      authentication: :plain
      user_name: "username@mars3142.org" 
      password: "password" 

but this didn't work. I didn't received any email.

OK, you want redmine to send mails.
What version of
- redmine
- ruby
- rails
do you use?

I'm on 1.4.3, but IMHO you need to remove tls: true for Redmine 2.0+.
Further, if I'm not mistaken "tls: true" mustn't be present when using Google Apps, it can break things even if enable_starttls_auto is true.

Hope that helps.
JN

[1] http://www.redmine.org/projects/redmine/wiki/EmailConfiguration
[2] http://mentalized.net/journal/2012/05/08/rails_3_actionmailer_and_google_apps_for_domains/

My system:

Environment:
  Redmine version                          2.0.3.stable.10309
  Ruby version                             1.8.7 (i686-linux)
  Rails version                            3.2.6
  Environment                              production
  Database adapter                         MySQL
Redmine plugins:
  no plugin installed

What should I set the authentication? On the two websites, there are two different settings.

  authentication: :login

  authentication: :plain

Now I recieved with the "test email function"

SSL_connect returned=1 errno=0 state=SSLv2/v3 read server hello A: unknown protocol.

And I did it, as described on http://goo.gl/LDTnP

And I did it, as described on http://goo.gl/LDTnP

Yeah, and you got exactly the same error message - have you really read the whole page?
Did you really delete the line tls: true?

I neither use Redmine 2 nor Google Apps, sorry I can't help further...

Sure, I read all:

production:
  email_delivery:
    delivery_method: :smtp
    smtp_settings:
      address: smtp.gmail.com
      port: 587
      domain: mars3142.org
      authentication: :plain
      user_name: "user@mars3142.org" 
      password: password
      enable_starttls_auto: true

Thanks for your help. Now I have a start to test it.