protected static function _deactivateOldModule()
    {
        $sModule = self::OLD_MODULE_ID;

        /**
         * @var oxModule $oModule
         */
        $oModule = self::_getModule();

        if ($oModule->load($sModule) === false) {
            self::_getUtilsView()->addErrorToDisplay(new oxException('EXCEPTION_MODULE_NOT_LOADED'));
            return false;
        }

        try {
            $oModuleCache = self::_getModuleCache($oModule);
            $oModuleInstaller = self::_getModuleInstaller($oModuleCache);
            return $oModuleInstaller->deactivate($oModule);
        } catch (oxException $oEx) {
            self::_getUtilsView()->addErrorToDisplay($oEx);

            if (method_exists($oEx, 'debugOut')) {
                $oEx->debugOut();
            }
        }

        return false;
    }