Sometimes I receive unusual but frustrating support requests. I help people using maxprog products mainly by responding to support tickets. That use to be a routine task I do every day with enthusiasm. It is almost the only contact I have with maxprog customers. However, sometimes I get unusual and frustrating requests. Unusual because hopefully, they are rare and frustrating because I really can't do anything to help because of the nature of the problem.
Unauthorized Purchases
First of those problems is fraud, somebody, somewhere with someone's credit card buying something on the maxprog store. Imagine who the victim will contact in the first place and what will be the tone and rudeness of the message.
The internet is a hostile place where gangs of angry delinquents will do everything to steal others' money. Usually, the victim is persuaded maxprog has debited its bank account or has used its credit card to purchase stuff without him knowing. But how and why would we do that? We are a respectable software seller, yes, but the victim doesn't care, he wants his money back.
My response is always the same here since we use Paypal and FastSpring card processors, the victim has to contact the appropriate people. Despite the purchase was to us, we have nothing to do with that, the victim has to open a formal complaint to either PayPal or FastSpring, explain the case and change passwords if necessary. Indeed its credit card data may have been stolen or its PayPal/FastSpring account credentials may have been compromised.
Compromised e-mail address or account
The second problem is spam, somebody, somewhere with someone mail account sending junk to thousands. Again, guess who the victim will contact?
Anyone with whatever email software can hack an email account and send stuff on your behalf. This is much more easy to do that you can imagine. We can do very little here. Indeed a software of ours may have been used but it was very likely a pirated copy. The people behind are very likely from some remote country you have never heard about and are hidden behind anonymous proxies.
Despite the difficulties in solving this type of claim we have been collaborating with the police of several countries, FBI, Scotland Yard, German Polizei, and Spanish Policía when our products were used to commit a crime. Maybe the best you can do if someone has used your account for criminal activities is to contact the police, they may have a web page in order to report such a thing.