If you remove the WHERE condition on country code and group by country code, it should return data all the countries. You may want to order the results by country code so you can easily look up countries in the CSV file.
SELECT [Country Code],
COUNT(DISTINCT(address2_fax)) AS [Count]
WHERE allowmail = 'Allow'
AND statuscode = '1'
AND l2g_brandname = 'Viviscal Max'
AND l2g_dispatcheddate >= CONVERT(DATETIME, '2012-09-01 00:00:00', 102)
AND l2g_dispatcheddate <= CONVERT(DATETIME, '2012-10-01 00:00:00', 102)