Login into your phpBB ‘Administration Control Panel’ as “Admin” user.
From the left side menu, Go to “General > CLIENT COMMUNICATION > E-mail settings”.
At the right side, under ‘SMTP settings’ section, Select ‘Yes’ to Use SMTP server for e-mail.
Under SMTP server address enter tls://mail.smtp2go.com.
Set the SMTP server port to 2525. You can also try using Server Port 25, 8025 or 587.
Select ‘PLAIN’ option from Authentication method for SMTP.
Enter your SMTP2GO SMTP user name into SMTP username and your SMTP password into SMTP password.
Click Submit to save your settings.
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