Hi All, I got AMD2 machine and VIsta 64 Ultramate. I found it's impossible to find codec to support RMVB for x64 vista media center. However there is no problem to play rmvb in WMP. So, I just think about whether I can force Vista X64 media center to use x32 WMP as player. I know by default vista media center is x64 application, and it uses x64 WMP. I also found Vista X64 component. There is a tools to use force media center to use 32bit WMP, but it doesn't work for me. It's appreciated if anyone have suggestions.