You can minimize the space occupied:-
The Symantec LiveUpdate Control Panel applet can configure how much space LiveUpdate will be able to use to store content updates.
1. Open the Control Panel.
2. Open the Symantec LiveUpdate applet.
3. Click on the Update Cache tab.
4. Move the slider for Maximum Cache Size all the way to the left.
5. Click the button to Remove All Files From Cache.
6. Click OK.
The button will remove all files currently in the C:\Documents and Settings\All Users\Application Data\Symantec\LiveUpdate\Downloads folder.
The next time that LiveUpdate runs, it will only keep files within the maximum size that is available.
Plan to move to 12.1