[VisualBasic] HILFE - Wieso funktioniert es nicht?

Option Explicit

' benötigte API-Deklarationen
Private Const VER_PLATFORM_WIN32s = 0
Private Const VER_PLATFORM_WIN32_WINDOWS = 1
Private Const VER_PLATFORM_WIN32_NT = 2

Private Type OSVERSIONINFO
 OSVSize As Long
 dwVerMajor As Long
 dwVerMinor As Long
 dwBuildNumber As Long
 PlatformID As Long
 szCSDVersion As String * 128
End Type

Private Declare Function GetVersionEx Lib "kernel32" _
 Alias "GetVersionExA" ( _
 lpVersionInformation As OSVERSIONINFO) As Long


Public Type WINVER
 OSVersion As String
 BuildNr As String
 ServicePack As String
End Type

' Windowsversion, Build-Nr und ServicePack ermitteln
Public Function GetWinVersion() As WINVER
 On Error GoTo ErrHandler

 Dim osv As OSVERSIONINFO
 Dim nPos As Integer
 Dim sVer As String
 Dim sBuild As String

 With GetWinVersion
 osv.OSVSize = Len(osv)
 If GetVersionEx(osv) = 1 Then
 Select Case osv.PlatformID
 Case VER_PLATFORM_WIN32s
 .OSVersion = "Win32s"
 Case VER_PLATFORM_WIN32_NT
 .OSVersion = "Windows NT"
 Select Case osv.dwVerMajor
 Case 5:
 Select Case osv.dwVerMinor
 Case 0
 .OSVersion = "Windows 2000"
 Case 1 
 .OSVersion = "Windows XP"
 End Select
 End Select
 Case VER_PLATFORM_WIN32_WINDOWS:
 Select Case osv.dwVerMinor
 Case 0
 .OSVersion = "Windows 95"
 Case 90
 .OSVersion = "Windows ME"
 Case Else
 .OSVersion = "Windows 98"
 End Select
 End Select
 
 .BuildNr = CSTR(osv.dwBuildNumber And &HFFFF&)
 nPos = InStr(osv.szCSDVersion, Chr$(0)) 
 If nPos Then
 .ServicePack = Left$(osv.szCSDVersion, nPos - 1)
 Else
 .ServicePack = "Kein Servicepack"
 End If
 End If
 End With
 On Error Goto 0

ErrHandler:
End Function

[B]Beispielaufruf:[/B]

Dim tWinVer As WINVER
tWinVer = GetWinVersion()
 
With tWinVer
 List1.AddItem "OSVersion: " & .OSVersion
 List1.AddItem "Build: " & .BuildNr
 List1.AddItem "ServicePack: " & .ServicePack
End With