Unable to connect to HTTPS secure site

Open up the web page for your modem and follow links to "Settings" : "System Info" : "Event Notifications".  If you have that page, turn everything off.  The notification is actually the modem attempting to hijack web pages and it breaks absolutely everything.   Certain conditions, like having a personal VPN server, result in constant false alarms.

This is not a gateway (router/modem) problem.  It is a security certificate problem.  Google NET::ERR_CERT_AUTHORITY_INVALID for various suggestions on how to address this.

ACE - thank you very much for your valuable reply. I followed the link you provided and looked over the material. I feel totally inadequate to the task of figuring out which of the many solutions is the one suited to my error/warning message. I found one that "looks" identical with the red satchel and white "X" on it... but the information provided and steps to follow is WAY over my head. Wishing to be more tech savvy - is there a "walk through" video of some sort or what would be my search criteria if I was googling to find one? Thanks for your help.

I have exact same problem.  Why no answers? 

We're here to assist with your connection concerns, @hecht661!

We recommend that you attempt to reset your gateway, as this can resolve a host of issues. These are the steps to take to reset your gateway:

1. Unplug the power cord from the back of your gateway or modem. If you have: 
   • An internal battery backup, remove it
   • DSL, unplug the phone cord from your modem or gateway
2. Wait 20 seconds.
3. Put the internal battery back in if you have one. 
4. Plug the power cord back in. If you have DSL service, reconnect the phone cord.
5. Wait for the gateway or modem to restart and your Broadband light to turn solid green. This can take up to 10 minutes.

If you need further assistance, please create a new thread along with more details as to what you are experiencing. The reason for this is this thread is subject to being closed at any mment due to it's age.

Let us know if you need further help!

CalebP, AT&T Community Specialist 

cold boot the modem. what a joke.....note to newbies....ignore att employee.

_xyzzy_ Answered just fine!!!!

@hecht661  Read  @_xyzzy_  Response.  He gave you the correct answer!!!

Click this:  https://www.google.com/search?q=NET%3A%3AERR_CERT_AUTHORITY_INVALID&ie=utf-8&oe=utf-8&client=firefox-b