Чувствительный к регистру VB 2012 с использованием msaccess

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он работает нормально,но не чувствителен к регистру. пожалуйста, помогите
моя база данных выглядит так [^]

Что я уже пробовал:

Imports System.Data.OleDb
Public Class loginmain
    Private conn As OleDbConnection
    Private dapt As OleDbDataAdapter

    Private Sub MyConnection()
        conn = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=" & Application.StartupPath & "\Data.accdb")
        conn.Open()


    End Sub
    Private Sub loginmain_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Watermark1.Focus()
        Panel5.Hide()
        Panel13.Hide()
        Label7.Hide()
        Label8.Hide()

        Timer1.Enabled = False
        Panel8.Hide()
        MyConnection()

    End Sub
    'form close
    Private Sub MyForm_Closing(ByVal sender As System.Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
        If MessageBox.Show(" Are you sure you want to quit?", " ", MessageBoxButtons.YesNo, MessageBoxIcon.Warning) <> DialogResult.Yes Then
            e.Cancel = True
        End If
    End Sub
    'PREVENT FLICKERING
    Protected Overloads Overrides ReadOnly Property CreateParams() As CreateParams
        Get
            Dim cp As CreateParams = MyBase.CreateParams
            cp.ExStyle = cp.ExStyle Or 33554432
            Return cp
        End Get
    End Property
    Private Sub PreVentFlicker()
        With Me
            .SetStyle(ControlStyles.OptimizedDoubleBuffer, True)
            .SetStyle(ControlStyles.UserPaint, True)
            .SetStyle(ControlStyles.AllPaintingInWmPaint, True)
            .UpdateStyles()
        End With

    End Sub

    Private Sub BunifuTileButton1_Click(sender As Object, e As EventArgs) Handles loginbutton.Click
        Dim pass1 As String
        Dim tbl As New DataTable
        MyConnection()
        dapt = New OleDbDataAdapter("Select * from UserAccount Where Username='" & Watermark1.Text & "'and Password='" & Watermark2.Text & "' ", conn)
        dapt.Fill(tbl)

        pass1 = Watermark2.Text
        If tbl.Rows.Count > 0 Then
            Timer1.Enabled = True
            Panel13.Show()
            Label7.Show()
            Label8.Show()

        Else

            My.Computer.Audio.PlaySystemSound(
                System.Media.SystemSounds.Exclamation)



            Panel5.Show()
            PictureBox2.Image = Payroll.My.Resources.Login_01error
            PictureBox3.Image = Payroll.My.Resources.User_Profileerror
           
            Watermark1.Focus()
            Watermark2.Clear()



        End If

    End Sub

   

    Private Sub PictureBox4_Click(sender As Object, e As EventArgs) Handles PictureBox4.Click

    End Sub

    Private Sub Watermark1_TextChanged(sender As Object, e As EventArgs) Handles Watermark1.TextChanged
        Panel5.Hide()

        PictureBox3.Image = Payroll.My.Resources.User_Profile1

    End Sub

    Private Sub Watermark2_TextChanged(sender As Object, e As EventArgs) Handles Watermark2.TextChanged
        Panel5.Hide()
        PictureBox2.Image = Payroll.My.Resources.password
    End Sub

    Private Sub LinkLabel1_LinkClicked(sender As Object, e As LinkLabelLinkClickedEventArgs) Handles LinkLabel1.LinkClicked

        ResetForm.ShowDialog()

    End Sub

    Private Sub LinkLabel2_LinkClicked(sender As Object, e As LinkLabelLinkClickedEventArgs) Handles LinkLabel2.LinkClicked
        ResetForm.ShowDialog()
    End Sub

    Private Sub LinkLabel3_LinkClicked(sender As Object, e As LinkLabelLinkClickedEventArgs) Handles LinkLabel3.LinkClicked
        Panel8.Show()
        Panel11.Hide()

    End Sub

    Private Sub BunifuTileButton1_Click_1(sender As Object, e As EventArgs) Handles RegBtn.Click

    End Sub

    Private Sub BunifuImageButton1_Click(sender As Object, e As EventArgs) Handles BunifuImageButton1.Click
        Me.Close()
    End Sub

    Private Sub Timer1_Tick(sender As Object, e As EventArgs) Handles Timer1.Tick

        loading.Value = loading.Value + 1
        Label6.Text = loading.Value & "%"
        Label8.Text = loading.Value & "%"
        If (loading.Value = loading.MaximumValue) Then
            System.Threading.Thread.Sleep(3000)

            Timer1.Enabled = False
            Me.Hide()
            MainForm.Show()
        End If
    End Sub

    Private Sub Panel4_Paint(sender As Object, e As PaintEventArgs) Handles Panel4.Paint

    End Sub
End Class

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