' Funktion definieren
Private Declare Function RegOpenKeyEx Lib "advapi32.dll" _
  Alias "RegOpenKeyExA" (ByVal hkey As Long, _
  ByVal IpSubKey As String, ByVal ulOptions As Long, _
  ByVal samDesired As Long, phkResult As Long) As Long
 
Private Declare Function RegQueryValueEx Lib "advapi32.dll" _
  Alias "RegQueryValueExA" (ByVal hkey As Long, _
  ByVal lpValueName As String, ByVal lpReserved As Long, _
  lpType As Long, lpData As Any, lpcbData As Long) As Long
 
Private Declare Function RegCloseKey Lib "advapi32.dll" _
(ByVal hkey As Long) As Long
 
' Current User Daten
Private Const HKEY_CURRENT_USER = &H80000001
' Lese zugriff
Private Const KEY_READ = &H20019
' Ein VBNullChar-Zeichen Terminierter String
Private Const REG_SZ = 1
 
Private Sub Command1_click()
 
      Dim Retval As Long, hkey As Long
      Dim TmpSNum As String * 255
 
      ' Pfand meiner gewünschte Registryeintrag in meinem Computer
      Retval = RegOpenKeyEx(HKEY_CURRENT_USER, _
    "Software\Microsoft\Windows NT\CurrentVersion\Windows Messaging" & _
    "Subsystem\13dbb0c8aa05101a9bb000aa002fc45a", _
    0&, KEY_READ, hkey)
 
    If Retval <> 0 Then
       MsgBox "Der Benutzerkonto konnte nicht geöffnet werden."
       Exit Sub
    End If
    ' Wert auslesen
    Retval = RegQueryValueEx(hkey, "001e3001", 0, REG_SZ, ByVal TmpSNum, Len( _
      TmpSNum))
       If Retval <> 0 Then
          MsgBox "Der Benutzerkonto konnte nicht gelesen oder gefunden werden."
          Exit Sub
       End If
 
        with UserForm1
         .Label1 = Left$(TmpSNum, InStr(1, TmpSNum, vbNullChar) - 1)
         End With
         ' Registry wieder schließen
         Retval = RegCloseKey(hkey)
 
End Sub