What that scary new red Gmail unlocked symbol means
Posted by Damien Biddulph on Wed 17th Feb 2016
In recent days, some Gmail users have been wondering and worrying about new emails popping up in their inboxes with a new unlocked icon.
Have no fear. As we mentioned on Tuesday, this is just Google's way of telling you that an email you've received isn't as secure as it should be.
Emails that have not been authenticated by TLS encryption (transport layer security) will show this red unlocked icon, but that doesn't necessarily mean that the sender is an evil spammer sneaking into your inbox.
What TLS encryption does is protect the security of email messages as they travel from sender to recipient. That encryption makes sure that the sender's email remains private, preventing third parties from taking a peek at the message or tampering with it as it makes its way to its final destination.