It seems like the lists are the right direction, but I get my error trying to get a response from CC server, so dot net returns the code, but no information. This is the string as I am sending to CC - MYACCOUNT is depersonalized activityType=SV_ADD&data=Email+Address%2cFirst+Name%2cLast+Name%0am1%40zmark.net%2cMark%2cZTesting1&lists=http%3a%2f%2fapi.constantcontact.com%2fws%2fcustomers%2fMYACCOUNT%2flists%2fBook+List
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