REPLY: I believe your problem could very well be that you have not adapted the OleCommandBuild er into your data adapter of your DataSet.
If you want to make your dataset to be able to make direct changes to the MS Access table, you need to enable the SQL UPDATE for your dataset and very important is that should be made before you apply the DataAdapter.Upd ate() method. To do this, OleCommandBuild er must be enabled to make yor DataSet open...