I downloaded a fresh copy of Codeigniter Version 2.1.3 and try to access welcome message page but I keep getting Error 324 ERR_EMPTY_RESPONSE in my browser (chrome) and in the other browsers i got blank (white screen) page."
I cleared the cache from browser. And I restarted the MAMP server. And it worked like charm in all browsers. :)
Hope this will help you as well.