Public Class Form1
    Private WithEvents tmr As New Timer
    Private messageTime As DateTime
    Private now As DateTime = Date.Now
    Private ts As New TimeSpan
 
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        messageTime = New DateTime(now.Year, now.Month, now.Day, 23, 35, 0)
        ts = messageTime - now
        tmr.Interval = ts.TotalMilliseconds
        tmr.Start()
    End Sub
 
 
    Private Sub tmr_Tick(ByVal sender As Object, ByVal e As System.EventArgs) _
      Handles tmr.Tick
        MsgBox("Messagebox um: " & messageTime.ToString)
        tmr.Stop()
    End Sub
End Class

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