Imports System.Data.OleDb
Public Class Form1
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim connetionString As String
        Dim connection As OleDbConnection
        Dim oledbAdapter As New OleDbDataAdapter
        Dim sql As String
        connetionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Your mdb filename;"
        connection = New OleDbConnection(connetionString)
        sql = "insert into user values('user1','password1')"
        Try
            connection.Open()
            oledbAdapter.InsertCommand = New OleDbCommand(sql, connection)
            oledbAdapter.InsertCommand.ExecuteNonQuery()
            MsgBox("Row(s) Inserted !! ")
        Catch ex As Exception
            MsgBox(ex.ToString)
        End Try
    End Sub
End Class