This vid helps Fix DLG_FLAGS_SEC_CERT_CN_INVALID while trying to access some website.
Case study 1: If you're the owner of the website, you need to re-insert the certificate, and you'll also need to do this every time when you do an update. For related info, please see goo.gl/tGCVM4. Case study 2: If you're a user of Chrome, Firefox and/or other browser on the web, try the below options. 1. Close the tab (website) and not visit the potentially risky site. 2. Clean local browser caches and try again, alter. 3. Try using a different browser. 4. contact site administrator and ask them to look into the issue on their end.