@emrevona
I think I found a workaround. I can’t fully test it because all my files haven’t been pushed to my S3 Bucket yet. But I get basic HTML from the CDN now…just waiting on my upload to finish for CSS and photos. I probably should have mentioned that my CDN is pointed to an S3 Bucket and there was no root page.
Here is what I did to make the plugin work:
1) I made an index.html file and simply put a comment inside it saying <!– This is to Prevent 403 Error Perms for WPFC Plugin –>
2) Save the file and upload it to the root of affected S3 Bucket
3) Now Click on the file and go to the Permissions tab of S3 Bucket and make sure everyone has only READ access on this file.
4) Now login to Stackpath, on left click CDN. Click domain name for affected CDN, now click Cache Settings. Click Purge everything.
5) Login back into wordpress and on the WPFC page click CDN. Select MAXCDN (Now Stackpath) for the URL Put: https://YOURCDNURL/index.html
6) The plugin will now get around the 403 error and ask you to select files, etc. Continue configuration as normal from here on.
Hope this helps somebody else, maybe sticky somewhere for people that run into the same issue.