What do you mean by an Error sound? One beep is normal on most systems. More than one indicates an error, but they need to be interpreted; a bit like Morse code! Further, each BIOS manufacturer tends to use different codes, so you need to know which BIOS is being used. You can see this on the very first screen at boot-up.
If the operating system is hanging at applying the security policy, it is likely that you have some software issue causing this. The quickest way to get a pointer to the problem is to go to; Start; Control Panel; Administrative Tools; Event Viewer and take a look at the logs.