[ChuckMcM]

File an FTC complaint about them, and a BBB one, and send a complaint to Dun & Bradstreet while you are at it, and post something on ripoffreport if they are still around. Then change your credit card # ( get a new number / card )

Sounds like these guys are exploiting the same flaw in CC payments that a number of phone services, domain name registrars, buyer protection services, etc exploit which is that there is no way to 'pre-decline' a charge to your credit card. They will keep charging your card (regardless of your cancellation) and when you complain they will send the CC company a copy of your initial signup / agreement and won't include any follow up documentation. You will have to send your email as documentation as 'proof' month after month. Many people just give up and pay the the money. The local news station has a consumerist segment they run now and then, this sort of scam comes up frequently.

Clearly you are not alone: http://www.ripoffreport.com/reports/directory/1and1-internet

[kintamanimatt]

Actually, my business bank in the UK (Barclays) can apparently block card payments in advance. I know because it took an astonishing amount of work to stop HasOffers from billing me after my trial had ended and been cancelled.

[mikeash]

Shouldn't even a somewhat small proportion of customers hitting them with chargebacks cause them to lose their merchant account fairly quickly? Is there some way around that, or does it just not work the way I think?