500 - Internal server error when including library in my controller

[eluser]Computerzworld[/eluser]
Thanks for the reply. This is my htaccess file.

Code:

RewriteEngine on
AddType application/x-shockwave-flash .swf
#RewriteBase /
RewriteCond $1 !^(index\.php|resources|robots\.txt|flash)
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?/$1 [L,QSA]

I am using CI 2.1.4. My library file name is MycustomLib.php and here is my controller's code for including & calling library function.

Code:

$this->load->library('MycustomLib');
$this->mycustomlib->dateDiff($eDate, $sDate);

When I am commenting out this code, it works fine.

Please let me know if you need anything else from my side.

Thanks.