Private Function GetUnixTimestamp() As Long
  ' Zeit-Differenz zum 01.01.1970 00:00:00 berechnen
  Dim nSek As Long
  nSek = DateDiff("s", CDate("01.01.1970 00:00:00"), Now)
 
  ' jetzt noch Sommern/Winterzeit berücksichtigen
  Dim nDiff As Long
  Dim st As SYSTEMTIME
 
  ' Systemzeit ermitteln
  GetSystemTime st
 
  ' Zeit-Differenz zur GMT-Zeit in Sekunden
  nDiff = DateDiff("s", DateSerial(st.wYear, st.wMonth, st.wDay) + _
    TimeSerial(st.wHour, st.wMinute, st.wSecond), Now)
  nSek = nSek - nDiff
 
  GetUnixTimestamp = nSek
End Function

Function GetUnixTimestamp() As Long
  Dim st As SYSTEMTIME
 
  GetSystemTime st
 
  GetUnixTimestamp = DateDiff("s", DateSerial(1970, 1, 1), DateSerial(st.wYear, _
    st.wMonth, st.wDay) + TimeSerial(st.wHour, st.wMinute, st.wSecond))
End Function