Nexcess (Error: Forbidding – You don't have permission to access /admin.php on this server)

Out of the blue this error popped up for me trying to upload an image in the CP (Forbidding – You don’t have permission to access /admin.php on this server). Needed to call Nexcess hosting support and they could fix the issue. Not sure what exactly they did but I heard term such as ModSecurity, Whitelisting things. Thought I post this here in case this happens to someone else using Nexcess and EE.