The outgoing server is the SMTP server, which delivers the emails to the receivers. There are issues related to the SMTP server.
- Step : 1 The SMTP server configuration for the email clients or email apps that you use may not support it. It is easy to solve, correct the configuration settings for the SMTP server.
- Step : 2 The SMTP port may be blocked for some reason, like increasing spam or high traffic. Usually, port 587 or 465 is used. Change the port and try to connect again.
- Step : 3 SMTP errors have codes to indicate the reason why an email cannot connect to the server. Some of the common error codes that occur are;
- Step : 4 421 - This code denotes that the email cannot be sent at this time because there are some issues with the receiver’s server policies. It can be because the receiver server became unreachable.
- Step : 5 450 - It means the receiver’s email address is no longer in use, or their server is rejecting the email due to filtering reasons.
- Step : 6 500 - This error occurs due to the installed firewall or antivirus. The security software would have rejected the emails for protection services.
- Step : 7 503 - This can appear due to the command that is executed in a wrong manner, which caused some error. For solving the error, it requires validation.
- Step : 8 552 - Sometimes, the email gets rejected for its huge size. The large-sized documents attached to the email is the cause of this error. So always keep the email size small.