Hello,
In your case, you would have to follow the Steps as below:
1) Download the Latest Version of SEP 12.0 from https://fileconnect.symantec.com
2) Once downloaded, you can Install Symantec Protection Center on your machine back.
3) Later there are 2 ways for get your clients Reporting back to the Symantec Protection Center
- You can Deploy the packages back to all the client machines http://www.symantec.com/docs/TECH93328 OR
- Get the Sylink.xml file and Run the SylinkReplacer Utility from the Server to all client machines.
https://www-secure.symantec.com/connect/downloads/sylinkreplacer-tool-connecting-sep-clients-sepm
NOTE: Incase, you are installing Symantec Protection Center on XP Pro machine, you need to know Windows XP has a 10 concurrent connection limitation that has been built in by Microsoft.
I personally would recommend you to install Symantec Protection Center on machine with Server OS (if any).
Check this Video on How to create client install packages with Symantec Endpoint Protection 12.0 SBE:
https://www-secure.symantec.com/connect/videos/how-create-client-install-packages-symantec-endpoint-protection-120-sbe
Hope this helps!!!