What Is Causing This Error?
The ‘error 451-4.4.2 timeout’ issue often occurs on sites using Gmail’s API to send emails. It indicates the connection between your SMTP server and the recipient’s email server was established successfully. However, the connection closed before sending the email due to a timeout.
This error can occur due to a variety of reasons. The most common causes are network issues, incorrect SMTP configuration, server overload, or firewall restrictions.
Resolving the Error – Solution
First, we suggest checking your internet connection. Oftentimes, these timeouts occur due to network issues. It may also happen due to server overload. In any case, we suggest waiting and retrying after a while.
If it doesn’t resolve the issue, you may need to check that your SMTP server is properly configured. Using the wrong port could potentially lead to a timeout error.
Another solution to the error is to check your hosting server’s firewall settings. Some web hosts have settings that block requests from SMTP servers.
So check and confirm that your firewall configuration isn’t blocking requests from your SMTP server. Be sure to contact your web hosting provider if you need help updating this setting.
That’s it! Now you know how to fix Error 451-4.4.2: Timeout – closing connection.
If you’d like to learn how to troubleshoot other common errors, check out the following tutorials: