$Date1 = "2006-10-10 20:06:22"
$Date2 = "October 11, 2006 8:06:23 PM"

fnDateDiff($Date1, $Date2, "s") ?
@SERROR ?

? "Press any key to continue." Get $
; 

Function fnDateDiff($sDate,$DateOrInterval,Optional $Interval,$Fix)
   Dim $objDateTime
   $objDateTime = CreateObject("WbemScripting.SWbemDateTime")
   If @ERROR Exit 10 EndIf
   $objDateTime.SetVarDate($sDate)
   If @ERROR Exit 1901 EndIf
   $sDate=$objDateTime.GetFileTime
   
   If InStr($DateOrInterval,"/") or InStr($DateOrInterval,":")
      $objDateTime.SetVarDate($DateOrInterval)
      If @ERROR Exit 1901 EndIf
      $DateOrInterval=$objDateTime.GetFileTime
      $fnDateDiff=(CDbl($DateOrInterval)-CDbl($sDate))/10000000
      Select
      Case $Interval="s"
      Case $Interval="m" $fnDateDiff=$fnDateDiff/60
      Case $Interval="h" $fnDateDiff=$fnDateDiff/3600
      Case $Interval="d" $fnDateDiff=$fnDateDiff/86400
      Case $Interval="w" $fnDateDiff=$fnDateDiff/604800
      Case 1 Exit 87
      EndSelect
      If $Fix $fnDateDiff=Fix($fnDateDiff) EndIf
   Else
      If VarType($DateOrInterval)>5 Exit 87 EndIf
      Select
      Case $Interval="s" If VarType($DateOrInterval)>3 Exit 87 EndIf
      Case $Interval="m" $DateOrInterval=$DateOrInterval*60
      Case $Interval="h" $DateOrInterval=$DateOrInterval*3600
      Case $Interval="d" $DateOrInterval=$DateOrInterval*86400
      Case $Interval="w" $DateOrInterval=$DateOrInterval*604800
      Case 1 Exit 87
      EndSelect
      $objDateTime.SetFileTime(''+(CDbl($sDate)/10000000+CDbl($DateOrInterval))+"0000000")
      If @ERROR Exit @ERROR EndIf
      $fnDateDiff=$objDateTime.GetVarDate
   EndIf
EndFunction