The 500 Error after registration means that Monster Tools Application isn't able to send activation email to users. 


You can disable User Activation from Settings > Users and disable "Activation Required" option from settings and then give it another try. If this fixes your problem then you can configure SMTP.

How to configure SMTP?

To configure SMTP go to Settings > Mail and click Use SMTP then enter your credentials. We highly recommend you to test your SMTP credentials using online tools, in Outlook or any other mail client so you know the correct port and encryption of your SMTP. When using online tools make sure you read the Privacy Policy so your SMTP is not compromised.


We highly recommend you to use Mail client for testing or you can use https://www.smtper.net/ SMTPER doesn't store your credentials so we recommend you to use that.



Popular SMTP Settings:

Gmail is widely used as SMTP, below are the correct SMTP settings for Gmail. If you have 2FA on your Gmail then your normal password will not work, you will need to generate Application based password

                                              

Incoming Mail (IMAP) Server

imap.gmail.com

Requires SSL: Yes

Port: 993

Outgoing Mail (SMTP) Server

smtp.gmail.com

Requires SSL: Yes

Requires TLS: Yes (if available)

Requires Authentication: Yes

Port for SSL: 465

Port for TLS/STARTTLS: 587

Full Name or Display NameYour name
Account Name, User name, or Email addressYour full email address
PasswordYour Gmail password


Yahoo SMTP Settings

  1. Server Address: smtp.mail.yahoo.com
  2. Username: Your Yahoo Address (e.g. example@yahoo.com)
  3. Password: Your Yahoo Password
  4. Port Number: 465 (With SSL)
  5. Alternative Port Number: 587 (With TLS)
  6. Authentication: Required
  7. Sending Limits: 500 Emails a day or Emails to 100 connections a day.

For further information please read here.