Hi Macropod,
Thanks for the quick response... however when i put in the code in and attempt to run it i get an "invalid procedure call or argument" runtime error (5) associated with the following line:
StrOld = .CustomDocumentProperties(MyProp).Value
is this because i need to create a custom field called MyProp? if so can you let me know how to do this, or fix the error?

i'd be very greatful.