Thats great thanks! I'm not sure what is going on here. I've tried two different domains, on the same virtual host, one in a sub domain and one in a root. Same outcome. So I know it's not specific to this installation but could be related to my virtual host. I have to say I have been with them over 10 years and I haven't had any odd issues like this before.
From the error I feel like it's something to do with how the POST XHR request is being handled; for some reason its being redirected to the internal 404 page. Now this only happens on the POST request not a normal http request. So it must be either how the POST request is being handled by the CMS code or maybe it's being manipulated by the .htaccess file. I wonder if it could due with the version of PHP I am on (7.3)? I have tried different browsers so I know its not browser related. I don't understand why its only happening in my case though, and why you can not recreate it. One thing I can recreate, is the 404 page as you can see in my screenshot, every time I reinitiate the POST request I hit the internal 404 page. Thanks again for your help! btw the way I am installing using the manual method not using Composure. Thanks so much for your help!
