Saving Data with DataAdapter to Jet DB

I am trying to save changes to a dataset using the dataAdapters update
method 
to an Access 2003 DB, therefore I'm using an OleDbDataAdapter to
accomplish 
this.
I am using a For/Next loop to change a single column of data in the 
dataTable, & I know this works. The problem arises when I try to write the

changes to the Access DB, nothing happens but the code process properly. I

use virtually the same code set in another project writing to a SQL server
DB 
& that works just fine. Is there some issue with OLEDB & Jet that this
does 
not work or that i must do something different?
Just for laughs I included a code snipit of what i'm doing.

        Try
            Conn.Open()
            daVoters.Update(dsCommittee, "Voters")
            Conn.Close()
            dsCommittee.AcceptChanges()
        Catch ex As OleDb.OleDbException
            Conn.Close()
            MessageBox.Show("There was an error updating the Database" & 
vbCr & vbLf & ex.Message, "Prep Data", MessageBoxButtons.OK, 
MessageBoxIcon.Error)

        End Try

BTW I can do this by writing each change to the DB as I change it in the 
datatable, but this requires me to open & close the connection nearly 1/2 
million times (there are over400,000 records in the DB)

Thanks
Gary