I am using Windows XP SP2 on my P4 1.5 GHz PC with 256 MB RAM and 40 GB HDD and BSNL Broadband connectivity. When I click shutdown option in start menu shut Down Windows dialogue box appears and when I select Shutdown or Restart and click OK, The window disappears and nothing happens, Windows continues working. I tried all the options I Know, but to shut down PC I am forced to press the Power button. I have a Background Story. I am using Norton AV 2003 Prof. and MS Antispyware software. One week back the NAV software shows an error message that It can't load some modules, because some other programs may trying to disable it, so NAV should be uninstalled and reinstalled. Before doing this I checked the registry and found windows/system32/antiav_exe.exe at startup. I removed the entry and deleted the file. I restarted the PC and checked again the registry found everything OK. Then I uninstalled and reinstalled the NAV and updated the NAV from Internet using Live update feature and restarted the PC. From that moment I am facing this problem. When I Uninstall the NAV the PC works fine. Again I reinstalled NAV and the problem started. I tried the NAV uninstallation and reinstallation procedure mentioned in Symantec support website, but the problem still exists. Is anyone experienced this problem before or is there any solution?