Fail installation of arduino duemilanove

Hello, i tried to install the arduino duemilanove in my laptop(win 7) but it cant install. It says that the driver is not installed when i plugged to the USB port. Im device manager, i cant see any port shows arduino board present. Only thing is 232 UART in other device in the device manger. When i open arduino, i see a message shows "Launch4j:an error occurred while starting the application". I went for troubleshooting section but i really cant find answer for my problem. Ur help really appreciated. Thanks.

You did a double post, please remove one thread , thank you