I have the folder there named 'json' and then I was trying to access the file under it, I got page not found error, but I rename the folder to some name such as 'data', then I can access the file under that folder.
Then in the renamed folder 'data' if I change the file name to 'json.php', then I got the page not found error again. If I rename the file back to 'data.php', then I can access it.
Does it have something to do with the CodeIgniter (CI forum said CI has nothing to do with it.) ? Very strange.
Or it is hosting set up issue? I am on a shared hosting with cpanel.