I think that Rick Strahl's west-wind web site has info on how to do this.

>Anyone doing credit card processing? I want to have users of my web site enter their information and not have to switch them to some other site. I want to keep the information on my server so that it will be easier to control access to the information and less headache to perform reconciliation with some external company.
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>Rather than contact any number of service providers and analyze their offerings, I thought I would approach this from the other direction and ask those who do credit card billing from Foxpro or other internet-aware software systems what their experiences have been and what companies perform well.