C#

try<br />
			{<br />
				cnnReturnBook.ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\IBS Library System\LibrarySystem.mdb;Persist Security Info=False";<br />
			<br />
				//Find the book that have to be returned<br />
				OleDbCommand cmdReturnBook = cnnReturnBook.CreateCommand();<br />
				cmdReturnBook.CommandText = @"SELECT * FROM BOOK<br />
											  WHERE RefNumber = '" + txtBookRef.Text + "' ";<br />
<br />
				OleDbDataAdapter daReturnBook = new OleDbDataAdapter(cmdReturnBook);<br />
				OleDbCommandBuilder cbReturnBook = new OleDbCommandBuilder(daReturnBook);<br />
<br />
				if ( daReturnBook.Fill(dtReturnBook) == 1 )//Book has been found, there should be only one 1 record in the datatable<br />
				{<br />
					//Clear the text boxes<br />
					txtDateOut.Text = "";<br />
					txtDateDue.Text = "";<br />
					txtStatus.Text = "Available"; //Show that the book is now available<br />
					txtIDNumber.Text = ""; //ID number of the student who has this book.<br />
					txtName.Text = "";<br />
					txtSurname.Text = "";<br />
<br />
					//Insert into the datatable row the new values<br />
					dtReturnBook.Rows[0]["Status"] = txtStatus.Text;<br />
					dtReturnBook.Rows[0]["DateOut"] = txtDateOut.Text;<br />
					dtReturnBook.Rows[0]["Remarks"] = txtRemarks.Text;<br />
					dtReturnBook.Rows[0]["StudentID"] = txtIDNumber.Text;<br />
					dtReturnBook.Rows[0]["DateDue"] = txtDateDue.Text;<br />
<br />
					daReturnBook.Update(dtReturnBook);//Error here<br />
				}<br />
			}<br />
			catch ( OleDbException ex )<br />
			{<br />
				MessageBox.Show(ex.ToString(),"Exeception has occurred",MessageBoxButtons.OK,MessageBoxIcon.Warning);<br />
			}<br />
			catch ( Exception ex )<br />
			{<br />
				MessageBox.Show(ex.ToString(),"Exeception has occurred",MessageBoxButtons.OK, MessageBoxIcon.Warning);<br />
			}<br />
			finally <br />
			{<br />
				cnnReturnBook.Dispose();<br />
			}<br />
		}