How to Find the Symantec Client product code:
The Symantec product code is the unique identifier for the product version and it can be found in the Windows Registry.
1) In the Windows Registry Editor, expand the following key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall
This key contains many <Product Code> keys.
2) In the left pane, click each <Product Code> key, and in the right pane look at the DisplayName value.
Find the <Product Code> key whose DisplayName value is “Symantec AntiVirus” or “Symantec Client Security”.
For example:
The product code for Symantec AntiVirus 10.0.0 is {5A633ED0-E5D7-4D65-AB8D-53ED43510284}
The product code for Symantec Client Security 3.0.0 is {E9FA3047-0B15-4E19-85CE-EE7FC6E60F99}