When a domain name hasn’t been configured correctly for email, Gmail may display a warning for emails from that domain, like this:
“Be careful with this message. Gmail could not verify that it actually came from . Avoid clicking links, downloading attachments or replying with personal information.”
If you’re a Gmail user and you’ve seen this warning, then do pay attention to the warning. It may be that the email is genuine, but if so, the organisation that sent it has not correctly configured their email systems to prevent spammers/phishers from mimicking their email address. This means even an email that looks genuine (with official looking branding etc) can actually be a fake email that has been edited, such as to modify some of the content or links.
If the email really is genuine, the organisation that sent the message needs to fix their email systems to tighten up security.