Hi G0AOZ,
This is Mike from the Norton Authorized Support Team.
First, I would suggest that you run Windows Update again to make sure you have all of the patches applied. Secondly, make sure the Windows Firewall is disabled so that it does not cause conflicts with Norton 360.
If your subscription is still active, you are entitled to a free upgrade to Norton 360 Version 2, which is highly encouraged.
Since you have installed Service Pack 3 while Norton 360 was installed, there is the possibility that it may have contributed to the problem. Therefore, I think the easiest way to resolve this issue is to first make note of your Norton 360 Activation Key, and to then properly uninstall Norton 360 version 1 and install Norton 360 version 2.
Please carefully follow the steps below.
1. Click on the following link to download the Norton Removal Tool:
Norton Removal Tool and Instructions
2. After you run the tool, please restart your computer. Then log in to Windows again and run the removal tool again. Restart your computer after it is finished running the second time as well.
3. Using Internet Explorer 5.5 or higher, click on the link below to visit the Norton Update Center to download the installer.
Norton Update Center
4. Once you have installed Norton 360 version 2, launch the application, click on the "PC Security" bubble and select "Check for Updates." When the updates are completed, please run a "Comprehensive Scan" on your computer to check for infections.
5. Lastly open the Windows Security Center and it should report that Norton 360 is handling the security for you.
Thanks,
Mike
Michael York
Norton Authorized Support Team
Symantec Corporation