Intermittently I have found the LuComServer_3_4.EXE process running on the computer and chews up a lot of CPU resources. As a result this slows down everything on the computer, often at a rather inconvenient time. What does this process do and how can I stop it from being such a resource hog? The computer is running Windows XP SP3.

LuComServer_3_4.EXE is the Symantec/Norton Live Update process. When this is running the Norton products on your computer (such as Norton Antivirus or Norton Internet Security) are checking for any updates, such as program updates or virus definition updates. Other users who experience this issue report that it can be stopped by disabling updates from within your Norton product. However, this is not a particularly long-term solution since not updating your security software (particularly, antivirus software) significantly reduces the amount of protection on your computer. Additionally, users have also reported that if you do disable automatic updates (thus terminating the LuComServer_3_4.EXE from running in the background) then trigger a manual update this process will commence execution again and stay running in the background.

Many people have reported issues with LuComServer_3_4.EXE consuming inordinate amounts of system resources causing the computer to slow down, but unfortunately apart from disabling this update server no one has provided a way to fix the issue. That said, it may be worthwhile checking the Symantec websites for any updates to the security software that you are running in case Symantec have released an update which can fix the issue. Alternatively, you may wish to investigate the latest versions of the Norton security line-up (as these claim to reduce the resource burden on your computer) or alternatively other competing antivirus products such as NOD32 or AVG.