Gmail account set up
Hi
I had two google mail accounts set up, and had to change the password on one. I removed the account, and can no longer add it back again, as I am getting the "Connection Insecure: Failed to verify the server certificate. This could be because of your network configuration or your proxy settings". I don't even get far enough to input the account email address.
I have checked for expired certificates, and I don't have any adblockers or antivirus installed, and my date and time are correct. The only difference I have made has been upgrading to High Sierra.
Help would be appreciated!
iMac (Retina 4K, 21.5-inch, Late 2015), OS X El Capitan (10.11.6)