Everyone has, or should have some type of antivirus software installed on their computer. With the constant barrage of viruses and spyware being created and sent out on the Internet you need to make sure that your software is up to date with the most current virus definitions so you don't become a victim.
The newer versions of Norton Antivirus enable you to have the program download and install the virus definitions automatically so you don't have to remember to do it.
But if you need to install the updates on multiple computers, a computer without an internet connection or a slow internet connection you can download the update file and put it on a USB flash drive or other removable media. This way you will not need to download it on every computer.
You can go to the following link to download the update file. Just make sure to select your product and version from the list before downloading the update.
After you select your version of Norton Antivirus simply click on the downoad link. It will then take you to a page where you can click the link to download the appropriate file. The Norton Antivirus update is an executable file that you simply double click and let it do the rest. It will display a conformation message when it completes successfully.
For Symantec products you can click the following link to get updates for your software.
Symantec's Virus Removal Tools
Read Up on the Latest Viruses From Symantec.com