Assume that you use ADO.NET Connection Manager to import data in Microsoft SQL Server 2012. However, if the columns that are expected by the Import and Export Wizard are missing, the import operation fails, and you receive the following error message:
Object reference not set to an instance of an object
In this situation, you have no way to know which columns are missing.
Service pack information
To fix this problem, get Service Pack 3 for SQL Server 2012.