VS2005 - C# - ADO.NET

I am unable to update an Excel worksheet that is contained in an Excel ODBC data source. The table is named "footanal".

I use the factory returned by DbProviderFactories.GetFactory(System.Data.Odbc) to create OdbcDataAdapter, OdbcConnection, and OdbcCommand object.

DbAdapter.SelectCommandText = "SELECT * FROM FootAnal";
DbAdapter.Fill(this.dataSetPatientsSessions.footanal);

I then create a new footanalrow object and assign values to its members.
Then, this.dataSetPatientsSessions.footanal.AddRow(mynewrow)

I use an OdbcCommandBuilder object to create an INSERT command and assign that to DbAdapter.InsertCommand;

Then, call DbAdapter.Update(this.dataSetPatientsSessions)

This is all within a try-catch block and there are no exceptions thrown.

When I open the Excel spreadsheet I observe

1. A new record has been added at the end of the sheet.
2. Most of the column headers (in row 1) have been replaced with #VALUE!
3. The values in most (but not all) of the columns have been replaced with #VALUE!

To try to debug this: before the call to Update, I asked the OdbcCommandBuilder object to create an UPDATE command. This did throw an exception which said:

"Dynamic SQL generation for the UpdateCommand is not supported against a SelectCommand that does not return any key column information"

I would appreciate help getting around this problem.

Thanks in advance for your help.

Jim