set the clock to the day before with a .vbs- thxs TNO

http://pastebin.com/3SmfjzcN

A Microsoft example of how to set the time to 2004 would be done like so which indicates there is a way to subtract a day
http://technet.microsoft.com/en-us/library/ee692591.aspx
 
On Error Resume Next
 
strComputer = "."
dtmNewDateTime = "20040520151300.000000-480"
Set objWMIService = GetObject("winmgmts:{impersonationLevel=impersonate, " _
 & "(Systemtime)}!\\" & strComputer & "\root\cimv2")
Set colOSes = objWMIService.ExecQuery("SELECT * FROM Win32_OperatingSystem")
 
For Each objOS In colOSes
  intSet = objOS.SetDateTime(dtmNewDateTime)
  If intSet = 0 Then
    Wscript.Echo "Successfully set new date and time."
  Else
    Wscript.Echo "Unable to set mew date and time."
  End If
Next
 
Set colOSes = objWMIService.ExecQuery("SELECT * FROM Win32_OperatingSystem")
For Each objOS In colOSes
  Wscript.Echo "New date and time: " & WMIDateToString(objOS.LocalDateTime)
Next
 
'******************************************************************************
 
Function WMIDateToString(dtmDate)
WMIDateToString = CDate(Mid(dtmDate, 5, 2) & "/" & _
                  Mid(dtmDate, 7, 2) & "/" & _
                  Left(dtmDate, 4) & " " & _
                  Mid(dtmDate, 9, 2) & ":" & _
                  Mid(dtmDate, 11, 2) & ":" & _
                  Mid(dtmDate, 13, 2))
End Function

You can use WbemScripting.SWbemDateTime (http://msdn.microsoft.com/en-us/library/aa394590(VS.85).aspx) to convert and manipulate the dates.  I believe it has a way to manipulate time\date with addition\subtraction as well.

I don't know why you are setting the date incorrectly, but you will not be able to log into an Active Directory domain if the computer time is 10 minutes diffrent from the AD controller.  In addition, the Windows Time service will automatically sync (if the computer is part of domain) the time and fix it.

Thxs rasimmer I finally found what I was after for the report
 
to subtract 1 day
dtmNewDate = Date - 1
Set objShell = CreateObject("WScript.Shell")
objShell.Run("%comspec% /c date " & dtmNewDate)
 
to add 1 day
 
dtmNewDate = Date + 1
Set objShell = CreateObject("WScript.Shell")
objShell.Run("%comspec% /c date " & dtmNewDate)