Flask mail only sending to certain domains

Question

I have a Flask application that uses an email server at Bluehost to send mail. Flask-mail successfully sends the email (I don't see any errors in the logs) however the email never arrives to Gmail accounts (not in spam or anything either). However, it does arrive at other domains.

Any idea what may be causing this or where to look for errors?

Thanks!

Answer 1

I just check your SPF records.

It seems that your sending mail server has no SPF record. This is why Gmail is probably blocking email from you mail server.

Check here for more info: this