invalid literal for int() with base 10: ” Nginx

I was doing changes to some pages the other day and I came across to an error when trying to update anything in django admin (these models use ImageField).

invalid literal for int() with base 10: ”

I googled for same issues but none of the fixes were working, until I decide to take a look to my nginx config file since I knew a few days ago I made some modifications. Right away I noticed that the following line was commented

#fastcgi_param  CONTENT_TYPE       $content_type;

After activating the line – restarted nginx and everything was back to normal.