Every few weeks, the users on our network receive a version of the following in Chrome, FireFox, and IE when trying to access gmail.com. All other SSL sites are fine.
The owner of www.google.com
has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.
This site uses HTTP Strict Transport Security (HSTS) to specify that Firefox may only connect to it securely. As a result, it is not possible to add an exception for this certificate.
When I restart our Windows 2012 server, restart the PCs, and flush the DNS, it goes away for a few weeks. Any ideas on a permanent fix?