Cookies for Multiple Sites

I’ve installed multisites on my website. When trying to set up my second site I can’t log in and get the following message:
Error: Cookies are blocked or not supported by your browser. You must enable cooking to use wordpress.

I have already tried:
1. Deleting cookies on my browser.
2. Added the following codes to my wp-config.php file:
define(‘COOKIE_DOMAIN’, false);
define( ‘COOKIE_DOMAIN’, $_SERVER[ ‘HTTP_HOST’ ] );

When I add any of the above codes, I get the following messages:

Warning: Use of undefined constant ‘COOKIE_DOMAIN’ – assumed ‘‘COOKIE_DOMAIN’’ (this will throw an Error in a future version of PHP) in /home/user/webapps/projectname/wp-config.php on line 97

Warning: Cannot modify header information – headers already sent by (output started at /home/user/webapps/projectname/wp-config.php:97) in /home/user/webapps/projectname/wp-login.php on line 504

Warning: Cannot modify header information – headers already sent by (output started at /home/user/webapps/projectname/wp-config.php:97) in /home/user/webapps/projectname/wp-login.php on line 520

Warning: Cannot modify header information – headers already sent by (output started at /home/user/webapps/projectname/wp-config.php:97) in /home/user/webapps/projectname/wp-includes/functions.php on line 6221