Error getting screenshot

I keep getting an error message when trying to capture a screenshot for sites being added. It doesn’t matter the URL and adding http:// or https:// doesn’t help at all. How can this be resolved. I’ve cleared cache both browser and server. And I have tried using Chrome, Firefox and Brave, nothing works.