You can review http://aumha.org/win5/a/shtdwnxp.php to see if you can fix it. But given the review standing of NIS 2004, you may have found why it's not doing well?
http://www.cnet.com/Norton_Internet_Security_2004/4852-3513_7-30524433.html
Bob
About six months ago I bought a Compaq 1.6 GHz P4 with 512 MB RAM, 80 GB HD running Windows XP Home. Since I have added a 120 GB external USB HD and a Pinnacle Video Capture Card. It came with Norton Anti Virus and when the subscription expired I renewed it. So I am running Norton System Works 2003 and Norton Internet Security 2004. I enabled a Live Update after which I kept getting a pop up message that Instant Messenger was not protected. I went to Help and following the instructions I re installed Norton. Now my machine will not shut down and sometimes it will not go to stand-by. I just hangs and displays the message that it is shutting down. I have to unplug the machine to restart it. Once running the machine seems to be OK. How can I fix this?

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