Error: SMTP error from remote mail server

What's Causing This Error

Multiple reasons can cause this error. The most common causes for this error are:

• Configuration errors.
• The sender's domain is present within the blocklist.
• Invalid recipients.

Solution - Here's How To Resolve It

To resolve this error, the user must ensure that they address the following potential causes:

1. Ensure that the configuration does not contain any errors.
2. Ensure that the sender's domain is not present within any blocklist. The recipient's email server administrator can attempt to check if the sender's domain is blocked.
3. Ensure there aren't any invalid recipients within the list of email addresses. It may also include duplicate email addresses.