Answer: From time to time we change field names or add new fields to the database tables. This error was caused by not having updated database fields. To fix this go to Database -> Connection & Data Fields.

There choose "Select All" under the Header & Detail Tables. Then "Test Configuration". Once that checks OK, hit "Save Field Configuration". Do this for each tab under the "Fields to be exported" tables. This will update your database to have all current fields & field names.