How to fix Gmail: 550-Please turn on SMTP Authentication in your mail client

If you encounter:

The error that the other server returned was: 550-Please turn on SMTP Authentication in your mail client, or login to the 550-IMAP/POP3 server before sending your message.

You may need to add 
include:_spf.google.com
to your SPF record.

Popular posts from this blog

How to delete / clear queue of PowerMTA