Redmine

When I customize mail settings in <redmine_install_dir>/config/configuration.yml and restart my servers, the Rails server(s) seem to start but then immediately stop.

I'm following the example for Gmail SMTP at http://www.redmine.org/projects/redmine/wiki/EmailConfiguration

I'm running a Bitnami native install of Redmine on Windows, using the "Bitnami Redmine Stack Manager" to restart all the servers.

Here's my environment as requested in the help forum sticky:

C:\Bitnami\redmine-3.0.4-1\apps\redmine\htdocs>SET RAILS_ENV=production

C:\Bitnami\redmine-3.0.4-1\apps\redmine\htdocs>ruby .\bin\about
DL is deprecated, please use Fiddle

Environment:
Redmine version                3.0.4.stable
Ruby version                   2.0.0-p645 (2015-04-13) [i386-mingw32]
Rails version                  4.2.3
Environment                    production
Database adapter               Mysql2
SCM:
Subversion                     1.8.11
Git                            1.9.5
Filesystem
Redmine plugins:
no plugin installed

C:\Bitnami\redmine-3.0.4-1\apps\redmine\htdocs>

Here are the settings I'm trying to use:

    email_delivery:
      delivery_method: :smtp
      smtp_settings:
        enable_starttls_auto: true
        address: 'smtp.gmail.com'
        port: 587
        domain: 'smtp.gmail.com'
        authentication: :plain
#        authentication: :login
        user_name: ‘MY_USRNAME@gmail.com'
        password: ‘MY_PWD’

I've tried changing the authentication value, which I've seen done differently in different examples.
I've tried omitting the domain value, which some examples seem to indicate is unnecessary for Gmail.
No luck.

I'm also not sure what the error is, so I don't know if I've made a mistake in syntax, or if it's a connection failure, or something else entirely. I've confirmed that I can telnet from my server to smtp.gmail.com on port 587. I don't see anything relevant in <redmine_install_dir>/log/production.log. Should I be looking someplace else?

Thanks so much.