Enabling SSL Causes Blank Page

[sperdie]

ZenCart Version v1.5.5e
This version was upgraded using official upgrade procedure (I think)
www.doma-italian-market.com
When I try to enable SSL (by changing the configure.php as in the code below) the page goes blank.
When I try to change the configure.php back to the way that it was- everything is still blank.
(I take out https: and clear cache) I have to restore a backup file of configure.php to get it working again.
The SSL appears to be in place as when I go directly to https://www.doma-italian-market.com the page loads with https successfully.
When I change the configure.php as below, the site url shows as https: but is blank.
Currently I have https server as follows with ssl set to false:

define('HTTPS_SERVER', 'https://sperdie.fatcow.com/doma-italian-market');

That is not the proper route for my shared ssl BTW. Its just what is there now. SSL was purchased for this domain with hosting company.

 // Define the webserver and path parameters
  // HTTP_SERVER is your Main webserver: eg, http://www.yourdomain.com
  // HTTPS_SERVER is your Secure webserver: eg, https://www.yourdomain.com
  define('HTTP_SERVER', 'http://www.doma-italian-market.com');
  define('HTTPS_SERVER', 'https:www//doma-italian-market.com’);
  // Use secure webserver for checkout procedure?
  define('ENABLE_SSL', ‘true’);

// NOTE: be sure to leave the trailing '/' at the end of these lines if you make changes!
// * DIR_WS_* = Webserver directories (virtual/URL)
  // these paths are relative to top of your webspace ... (ie: under the public_html or httpdocs folder)
  define('DIR_WS_CATALOG', '/');
  define('DIR_WS_HTTPS_CATALOG', '/');
  define('DIR_WS_IMAGES', 'images/');
  define('DIR_WS_INCLUDES', 'includes/');
  define('DIR_WS_FUNCTIONS', DIR_WS_INCLUDES . 'functions/');
  define('DIR_WS_CLASSES', DIR_WS_INCLUDES . 'classes/');
  define('DIR_WS_MODULES', DIR_WS_INCLUDES . 'modules/');
  define('DIR_WS_LANGUAGES', DIR_WS_INCLUDES . 'languages/');
  define('DIR_WS_DOWNLOAD_PUBLIC', DIR_WS_CATALOG . 'pub/');
  define('DIR_WS_TEMPLATES', DIR_WS_INCLUDES . 'templates/');
  define('DIR_WS_PHPBB', '/');