yesterday I worked on the online install of WP multisite after a try on local. The WP is not at the root of the website but at an address like wwww.domaine.com/wordpress/ http://www.domaine.com is a corporate website.
Installation went fine until I create a new website. Once this website created, I was not able to access (error 404 or 500 internal server error) his admin dashboard & the new website got no theme apply on it.
I look over forum to get an answer, nothing matching my case.
I decided to deleted using a ftp client the folder from the website, and upload a .htaccess whithout the change done during the installation
Now the main website display a blank page.
First I want to get http://www.domaine.com working without the blank page, then I'll have a look at the WordPress install.
Thanks for your support.