"we are unable to run the Audio/Video tuning Wizard at this time"

Hi, after I installed msn 7.0.0816 final version, I can not start
video/audio conference:
when I click on webcam settings it`s ok, but on audio/video tuning wizard
I got that error:

"we are unable to run the Audio/Video tuning Wizard at this time"

"Impossibile eseguire la Regolazione guidata audio/video" (this is the
message in my italian version of msn)

but I am able to that with other messenger pros,

I have xp pro sp2 and all necessery updates done.
ports which are needed for msn messenger open.


any help,

thanks in advance....