Public Declare Function ShellExecute Lib "shell32.dll" Alias "ShellExecuteA" ( _
      ByVal hwnd As Long, _
      ByVal lpOperation As String, _
      ByVal lpFile As String, _
      ByVal lpParameters As String, _
      ByVal lpDirectory As String, _
      ByVal nShowCmd As Long) As Long
 
    Private Const SW_HIDE = 0
    Private Const SW_MAXIMIZE = 3
    Private Const SW_MINIMIZE = 6
    Private Const SW_NORMAL = 1
    Private Const SW_SHOW = 5
    Private Const SW_RESTORE = 9
    Private Const SW_SHOWMAXIMIZED = 3
    Private Const SW_SHOWMINIMIZED = 2
    Private Const SW_SHOWMINNOACTIVE = 7
    Private Const SW_SHOWNA = 8
    Private Const SW_SHOWNOACTIVATE = 4
    Private Const SW_SHOWNORMAL = 1
 
    Private Const ERROR_BAD_FORMAT = 11&
    Private Const SE_ERR_ACCESSDENIED = 5
    Private Const SE_ERR_ASSOCINCOMPLETE = 27
    Private Const SE_ERR_DDEBUSY = 30
    Private Const SE_ERR_DDEFAIL = 29
    Private Const SE_ERR_DDETIMEOUT = 28
    Private Const SE_ERR_DLLNOTFOUND = 32
    Private Const SE_ERR_FNF = 2
    Private Const SE_ERR_NOASSOC = 31
    Private Const SE_ERR_OOM = 8
    Private Const SE_ERR_PNF = 3
    Private Const SE_ERR_SHARE = 26
 
 
 
    Private Sub startt(ByVal da As String)
        Dim Retval As Long
 
        Retval = ShellExecute(0, "open", "c:\Bug.txt", "", "", SW_SHOWMAXIMIZED)
 
 
 
        Select Case Retval
            Case SE_ERR_NOASSOC
                MsgBox("Datei ist nicht Assizoiert", vbInformation, "Fehler")
                Exit Sub
            Case SE_ERR_PNF
                MsgBox("Pfad wurde nicht gefunden", vbInformation, "Fehler")
                Exit Sub
            Case SE_ERR_FNF
                MsgBox("Datei wurde nicht gefunden", vbInformation, "Fehler")
                Exit Sub
            Case 8, 26, 32, 28, 29, 30, 27, 5, 11 ' alle anderen Fehler
                Exit Sub
        End Select
 
    End Sub