Add Image Button – 403 Access denied

I have tried removing the theme and all plugins and still the same issue. I even installed a subdomain and put a fresh wordpress site on there and I get the same issue 403 error

403 forbidden means that your browser isn’t able to load the scripts up because your server isn’t allowing it. This is a hard one to solve. Because anything could be blocking the server:
– Most likely this is a server permissions/ownership issue, so ask your host what’s going on.
– Another possible cause could be a corrupt .htaccess file. Also check your .htaccess files for anything strange.
– make sure your server settings are not overriding the .htaccess file.
– Another possible cause could be accidental changes to the server settings. Check with your hosting provider.

@t-p thank you for the reply! I have tried recreating the htaccess, checked permissions, and been talking to the hosting company for a few days now.

Do you know possibly what I could recommend they try?

They should know their servers better than anybody.

Just ask them to find the cause and fix it.

Its unlikely this issue has anything to do with WP core.

Have you checked the error logs on your server for a more specific error message and see why it’s failing? If you need help locating them, ask your hosting provider to help you with that.

If you cannot find error logs or if you don’t find any helpful info in the error logs, try Enabling debugging

@t-p They are insistent that they are able to post images fine from there end. But I have tried different computers, VPSs, Different browsers.
In the dev mode it says 403 error linked to ajax could there be some restrictive code that got added to that by a security plugin or something?