- First look in includes/application_top.php and find this line
// define the project versionUnder that will be a line that starts with define('PROJECT_VERSION'. These are the main choices:
define('PROJECT_VERSION', 'osCommerce 2.2-MS1'); //released prior to July/2003
define('PROJECT_VERSION', 'osCommerce 2.2-CVS'); //released between the above/below dates
define('PROJECT_VERSION', 'osCommerce 2.2-MS2'); //released after July/2003
define('PROJECT_VERSION', 'osCommerce Online Merchant v2.2 RC1'); //released March/2007
define('PROJECT_VERSION', 'osCommerce 3.xxx'); //not released for general use
The versions before MS2 are not compatible with MS2, which is the main version is use. Between MS2 and RC1, there were two patch updates. There isn't a version number for those patches (in the files) so you have to compare file content to see if they are installed. First, download the patches from here. Extract the contents and compare a few of the files with those in your shop. If your shop has them installed, then you probably have the latest MS2 version.