Error trying to update plesk 8.3 to plesk 9.0

[estanis]

Hello.
I'm trying to update my plesk panel from 8.3 to plesk 9.0 and i recieve this error: windows cannot open this program because the license enforcement system has been tampered with or become corrupted.

I downloaded the file from parallels website.
If i try to update the plesk from 8.3 to 8.6 i recieve the same error.
Does anyone knnows why?
Thank you.