Greetings,

  I am working on making the transition from NVP submissions to the new AIM XML submissions.

  I began working with a new sandbox account as its my understanding that all sandbox accounts now have the ability to test both CNP and CP transactions - which is what m real retailer will have.

 My initial tests sending a string which includes track data is consistently returning error code "The Market Type is invalid".

 I can not find any settings within the sandbox merchant account to enable a CP AIM string with track data.

 Possible error points - does my track data string need editing so that the test card numbers are used?

 Or is the track data in some way rejected?  

 I've tried removing the first/last characters from the track data and see no change in the error code.

  Thanks for any additional ideas.