Dear Reader,

I have a DataGridView control on my form and when it's shown, the following
error is shown:

"System.ArgumentException: DataGridViewComboBoxCell value is not valid."

The DataGridView's datasource is set using the following code:
************************************************************
dataGridViewPersons.DataSource = businessLayer.GetListOfPersons(initialise,
companyID);
       if (dataGridViewPersons.DataSource != null)
       {
          dataGridViewPersons.Columns["ID"].Visible = false;
          dataGridViewPersons.Columns["ID_Company"].Visible = false;
       }

public BindingSource GetListOfPersons(bool initialise, string companyID)
   {
     SqlCommand sqlCommand;
     DataColumn dataColumn;

     try
     {
       if (initialise)
       {
         sqlCommand = new SqlCommand();
         sqlCommand.CommandText = "SELECT * FROM tblPersons";
         sqlCommand.Connection = sqlConnection;

         dataSetPersons.Clear();
         sqlDataAdapterPersons = new SqlDataAdapter(sqlCommand);
         sqlCommandBuilderPersons = new
SqlCommandBuilder(sqlDataAdapterPersons);
         sqlDataAdapterPersons.Fill(dataSetPersons, "Persons");

         dataColumn = new DataColumn("FullName");
         dataColumn.Expression = "IIF( Len([FirstName]) >= 1,
TRIM([FirstName]) + ' ', '') + " +
                                 "IIF( Len([MiddleName]) >= 1,
TRIM([MiddleName]) + ' ', '') + " +
                                 "IIF( Len([LastName]) >= 1, [LastName],
'')";
         dataSetPersons.Tables["Persons"].Columns.Add(dataColumn);

         bindingSourcePersons = new BindingSource();
         bindingSourcePersons.DataSource =
dataSetPersons.Tables["Persons"].DefaultView;
       }
       else
       {
         bindingSourcePersons.Filter = "ID_Company = " + companyID;
       }

       return (bindingSourcePersons);
     }
     catch (Exception exception)
     {
       errors.Add(exception.Message);
     }

     return (null);
   }
************************************************************
To the datagrid a colums is added:
************************************************************
cmbGender = new System.Windows.Forms.DataGridViewComboBoxColumn();
     cmbGender.DataPropertyName = "Gender";
     cmbGender.HeaderText = "Gender";
     cmbGender.Name = "cmbGender";
     cmbGender.Width = 100;
     cmbGender.Items.AddRange( new string[] {"Male", "Female"} );
     dataGridViewPersons.Columns.Add(cmbGender);

************************************************************
Question: How can I solve this error???

Thank you!

Johan Machielse
Ordina SI&D - DCM