![Using Devise with Gmail, SendGrid, Rails and Heroku: Tips to save time debugging | by Cheney Shreve | Medium Using Devise with Gmail, SendGrid, Rails and Heroku: Tips to save time debugging | by Cheney Shreve | Medium](https://miro.medium.com/max/1400/1*VrpjZ-7-RnxdcNJGUl7Fzg.jpeg)
Using Devise with Gmail, SendGrid, Rails and Heroku: Tips to save time debugging | by Cheney Shreve | Medium
actionmailer 3.2.13 requires "mail ~> 2.5.3" breaking compatibility · Issue #9780 · rails/rails · GitHub
Error connecting to SMTP - hostname does not match the server certificate · Issue #1662 · bigbluebutton/greenlight · GitHub
Chatwoot - SMTP email does not work with environment variables · Issue #180 · caprover/one-click-apps · GitHub
![How to verify that SSL for IMAP/POP3/SMTP works and a proper SSL certificate is in use – Plesk Help Center How to verify that SSL for IMAP/POP3/SMTP works and a proper SSL certificate is in use – Plesk Help Center](https://support.plesk.com/hc/user_images/vjwyZ1jR0MBJyseMoE3RiA.png)
How to verify that SSL for IMAP/POP3/SMTP works and a proper SSL certificate is in use – Plesk Help Center
openssl_verify_mode=>"peer" can cause OpenSSL::SSL::SSLError: SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verify failed · Issue #1076 · mikel/mail · GitHub
![ruby - Easy Redmine SMTP configuration error: An error occurred while sending mail (SSL_connect returned=1 errno=0 state=error: certificate verify failed) - Stack Overflow ruby - Easy Redmine SMTP configuration error: An error occurred while sending mail (SSL_connect returned=1 errno=0 state=error: certificate verify failed) - Stack Overflow](https://i.stack.imgur.com/H19iR.png)