When mapping a field that may contain blanks, receiving an error that says “eConnect expected a value and none was supplied”.

You need to create a calculated field and use it in your mapping. So for instance if the column name is called TAX_CODE, and occasionally it contains a blank, your calculated field would look like this. if _TAX_CODE=”” then return string.Empty else return _TAX_CODE end if Then you map your calculated field to the appropriate destination field in your mapping.