There seems to be a problem in how empty DataSets handle new rows in .Net 2, we received an exception with the message “DataTable internal index is corrupted”. Our realy simple solution is to call BeginLoadData before adding the new row and then EndLoadData afterwards. This fixed the problem for us, but the actual status of the bug can be found here: http://lab.msdn.microsoft.com/productfeedback/viewfeedback.aspx?feedbackid=ecc665a5-d71a-4e08-ac42-f3c6c5d758e0 Read more »