Animate CC 2020 no longer outputs for testing in a browser after a new untitled document is saved.

I'm running Adobe Animate CC 2020 on an iMac running OS Mojave 10.14.6.  The softwear use to work just fine.  But now it only works fine on a newly created untitled and unsaved document.  As soon as I save the new untitled document,  Animate no longer outputs the document for testing it in a browser.  Instead, I get the message below everytime I try to test in a browser a newly saved Animate document....

I've restarted my computer several times  and checked for Animate softwear updates, but I continue to get the same output error message everytime after saving a newly created untitled and unsaved Animate document. As long as I don't save a new untitled Animate document the softwear works fine with creating it and outputing it for testing it in browser. But if I save the document, I loose the ability to output the document for testing in a browser to see if my animation is working as I'm creating it to work.  Is there a solution for this problem?