Installation problem with the new Realplayer ( access problem to the registry)

Hi,
When I am installing the new Real player from real.com, with either on the web installer or the full one, getting the following unusual error: "you currently do not have administrator access to the windows registry. Please see you system administrator to install realplayer".
It is unusual because I’m the admin of my PC, and I do access the registry and modify as I want. I have tried with uac enabled/disabled, with all kinds of safe mode, but still can’t get rid of this message. For your information, I’m using windows vista ultimate sp2.
So far I have never faced with any kinds of problem with installing programs, with or without uac. Again, I can install the older versions of the player with no problem, but not the new one. I try to use the real online solution, but did not find any solution. Please help me out.
