[ruby-on-rails] 535-5.7.8 Username and Password not accepted

I have a contact form and after submitting I am getting a Net::SMTPAuthenticationError 535-5.7.8 Username and Password not accepted

It's pointing to the create action in the contacts controller ContactMailer.new_contact(@contact).deliver

I have restarted the server. I tried https://accounts.google.com/DisplayUnlockCaptcha.

I am in development.

Contacts controller:

 def new
      @contact = Contact.new
    end

    def create
      @contact = Contact.new(params[:message])
      if @contact.valid?
        ContactMailer.new_contact(@contact).deliver
        flash[:notice] = "Message sent! Thank you for contacting us."
        redirect_to root_url
      else
        render :action => 'new'
      end
    end
  end

Development.rb:

  config.action_mailer.raise_delivery_errors = true
  config.action_mailer.perform_deliveries = true
  config.action_mailer.delivery_method = :smtp
  config.action_mailer.smtp_settings = {
    address:              'smtp.gmail.com',
    port:                 587,
    domain:               'gmail.com',
    user_name:            '[email protected]',
    password:             'password',
    authentication:       'plain',
    enable_starttls_auto: true  }

  config.action_mailer.default_url_options = { :host => "localhost:3000" }

UPDATE:

Notice: This setting is not available for accounts with 2-Step Verification enabled, which mean you have to disable 2 factor authentication.

If you disable the 2-Step Verification:

• Open your Gmail account in browser
• Navigate to Less secure app access
• Make Allow less secure apps => On

Time flies, the way I do without enabling less secured app is making a password for specific app

Step one: enable 2FA

• https://myaccount.google.com/signinoptions/two-step-verification/enroll-welcome

Step two: create an app-specific password

• https://myaccount.google.com/apppasswords

After this, put the sixteen digits password to the settings and reload the app, enjoy!

  config.action_mailer.smtp_settings = {
    ...
    password: 'HERE', # <---
    authentication: 'plain',
    enable_starttls_auto: true
  }

If you still cannot solve the problem after you turn on the less secure apps. The other possible reason which might cause this error is you are not using gmail account.

-    : user_name  =>  '[email protected]' ,  # It can not be used since it is not a gmail address 
+    : user_name  =>  '[email protected]' ,  # since it's a gmail address

Refer to here.

Also, bear in mind that it might take some times to enable the less secure apps. I have to do it several times (before it works, every time I access the link it will shows that it is off) and wait for a while until it really work.

Goto config/initializers/setup_mail.rb Check whether the configuration there matches the configuration written in the development.rb file.It should look like the following in both files:

config.action_mailer.smtp_settings = {
     :address =>"[email protected]",
     :port => 587,
     :domain => "gmail.com",
     :user_name => "[email protected]",
     :password => "********",
     :authentication => 'plain',
     :enable_starttls_auto => true,
     :openssl_verify_mode => 'none' 
     } 

This will most certainly solve your problem.

I had the same problem. Now its working fine after doing below changes.

https://www.google.com/settings/security/lesssecureapps

You should change the "Access for less secure apps" to Enabled (it was enabled, I changed to disabled and than back to enabled). After a while I could send email.

In my case removing 2 factor authentication solves my problem.

I did everything from visiting http://www.google.com/accounts/DisplayUnlockCaptcha to setting up 2-fa and creating an application password. The only thing that worked was logging into http://mail.google.com and sending an email from the server itself.