Dejar aplicación en administrador de tareas

 Imports System.Reflection

Private Declare Function ShowWindow Lib "user32.dll" (ByVal hWnd As IntPtr, ByVal nCmdShow As Integer) As Boolean


Public Shared Sub HideWindow()
        Dim SW_HIDE As Integer = 0
        For Each pr As Process In Process.GetProcesses
            If pr.ProcessName.Contains("AcroRd32") Then
                'Int32 hWnd = pr.MainWindowHandle.ToInt32();
                ShowWindow(pr.MainWindowHandle, SW_HIDE)
            End If

        Next
    End Sub


Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
      HideWindow()
 End Sub

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