The 207 (net::ERR_CERT_INVALID)Unknown Error is a mystery, but you can check these things to insure that the cause of the error is not your local computer.
1. Insure that the date and time are correct on your system clock. You should be able to right click the time and click the menu to "adjust date/time".
2. insure that your Chrome is updated properly. Also clear the Internet cache, then restart the browser.