I add an access database to use in my form, later I add more columns through "DataSet.xsd" then I update the datagrid, now they are also shown ... but when I try to add values in this new fields, seems to be saved but if I reload or select another index, the filled values of the last added columns get loose, just the original fields are saved. What i missing?
Don't add columns directly to your DataSet. That just changes the DataSet. It has no effect on the database. What you should have done is added the columns to the database and then rerun the configuration wizard from the Data Sources window. That would then refresh the DataSet with the new schema from the database.