I am having the Same 'Connection Error : General Error' on any Online banking setup I'm trying to do In Quickbooks for Mac 2019. It was working in Quickbooks 2017 but now its not working in Quickbooks 2019 v18.0.6 R7.

I've tried setting up a new company and that didn't seem to make a difference. I can log into each banking website in a browser with the same credentials. 

Any help would be great.

Scott-