The Server Responded 550 Access Denied – Invalid HELO Name See RFC 2821 4.1.1.1

I was getting this error and quickly found a solution, but I wanted to share this with folks, should they also get the error. If you’re setting up an IMAP account, the first step will be to create the account, the next step will be to verify the settings. The verification will work, but the test email will fail, throwing this error:

The Server Responded 550 Access Denied – Invalid HELO Name See RFC 2821 4.1.1.1

 

To fix this, make sure you’re using SMTP. Here’s how:

1. When configuring the account, choose More Settings.
2. Click on the Outgoing Server tab and check the box that says: My outgoing server (SMTP) requires authentication.
3. No need to enter anything else. Apply the changes and you’ll be fine.

Explained…

If you log into your cPanel, if you have one, you’ll see how to configure the account, notice in the settings it specifically says authentication will be required:

 

So, to accomplish this, we tell the client that it is required. It will do the duty on its own.

Your next test will be fine:

 

I hope this helps some folks.

Cheers!