ASP.net MVC5 project won't work on webserver (Plesk)

Question

So I recently published my MVC5 application to Plesk + GoDaddy. But no matter what I try, I always get this error:

The page you tried to access does not exist on this server. This page may not exist due to the following reasons:

• You are the owner of this web site and you have not uploaded (or incorrectly uploaded) your web site. For information on uploading your web site using FTP client software or web design software, click here for FTP Upload Information.

• The URL that you have entered in your browser is incorrect. Please re-enter the URL and try again.

• The Link that you clicked on incorrectly points to this page. Please contact the owner of this web site to inform them of this situation.

I've searched the web and tried various solutions but they won't work, like editing web.config file, editing global.asax file, setting the 'CAS trust level' to 'Full' etc etc.

I can't wrap my head around it. Am I overlooking something?

EDIT: this is the exact error message page I am getting

Answer 1

After all it was the connection string which was wrong.