I'm getting this error message:

An unhandled exception of type 'System.InvalidCastException' occurred in system.windows.forms.dll

Additional information: Object cannot be cast from DBNull to other types.

This occurs when I click on the add new record button on the form on which I have check box controls bound to the dataset. I've realised that this maily happens because the fields in the database are null. In the database, the field type is 'bit'. I'm using SQL Server 2000. I tried setting the default values to zero in the database but still problem is not resolved. Somebody pls help. I'm stuck.