Table: Methods to obtain updated definitions from Symantec
How often Symantec provides updated definitions
Use LiveUpdate to automatically update your protection. When LiveUpdate runs, it only downloads and installs the definitions that are more current than the definitions that are found on the Symantec Protection Engine server.
You can configure LiveUpdate to run on a scheduled basis, or you can run it manually.
You can use more than one method at a time to update your protection. You do not have to choose one or the other. For example, you can perform on-demand LiveUpdate definition updates and schedule Rapid Release definition updates to occur simultaneously.
You must have a valid content license to install definition files. A content license is a grant by Symantec Corporation for you to update Symantec corporate software with the latest associated content, such as new definitions. When you do not have a content license or your license expires, your product does not receive the most current definitions. Outdated definitions can leave your servers vulnerable to risks.