OptionButton Macro not functionning correctly

Hi team,


This should be an easy one but for some reason part of my macro is not functionning ONLY on windows XP machines..When I try on windows 7 everything is ok..

So basically the bellow code is supposed to take the value of my optionbutton (True or False) in a UserForm and if the value is true then it puts an X on tab Quality Grid
range G22..Why isn't this working on windows xp machines? Not giving me any errors ..the X just doesn't show after I submit form.

Sub Extract()

Dim iRow As Long
Dim Ws As Worksheet
Dim QG As Worksheet
Set Ws = Worksheets("Evaluation Tracker")
Set QG = Worksheets("Quality Grid")



If Me.OptionButton15.Value = "True" Then 'OptionButtons 3 Year Term
qa.Range("G22") = "X"

End IF
End Sub