Using trust center in Office 2007

[Ronny]

I am trying to change some parameters in the Trust Center both in Excel2007
and Word2007 and the changes are not saved when I leave Trust Center. The
behaveiour is as follows (in Word):
I open Trust Center,
go to "Trust Ceter Settings"
change the Macro settings,
"OK" the changes.
when I go back in either after leaving Word and saving the document of
immediately, the selection in macro settings revert to the one before the
change. Same happens if I try to change the trusted locations or any other
value.
The computer is a laptop standalone running windows vista ultimate.