Subdomain involuntarily redirects to primary domain after logging in or saving I made a development site using development.breinwijzer.be as subdomain. After I've logged in, I'm already back at my primary domain www.breinwijzer.be.


I tried different browsers.   
I cleared caches.  
I cleared browser caches.  
I checked the settings.php file of the development site to see if I have the correct database set for the development site.   


Other than this, I'm clueless.
In the settings.php someone uncommented $base_url and put the primary domain of the site as a value. Changing the value into the subdomain I was working in solved the issue.