Campaigner.com - Email broadcast software

An account was activated by mistake back in December 2006, but the account was not used at all by our company. Once we realized that mistake later in August, we contacted campaigner.com to let them know about the error but they refused to refund the credit card charges ($320), even if they can easily check that the account was not used at all. We were ready to use the system again but decided against using campaigner.com because of their lack of goodwill and understanding. We don't think this is the right way to build a long-term positive relationship with a customer.