For Avast Antivirus Users
If you’re an Avast Antivirus user then you can add the site giving you this error to your Avast exclusion list. Sometimes about Avast seems to be triggering this error so to fix the issue we just tell Avast to ignore the pages that it does not like and the error disappears.
Open Avast in your desktop
Click on Settings
Click on Active Protection
Click on Customize for Web Shield Protection
Add each website separately to the URLs to exclude section.