follow the steps from this link
http://symantec.com/docs/TECH190901
To Enable the "Computer Browser" service, follow the steps below:
1) Click on "Start"
2) Click on "Run"
3) Type "services.msc" (without quotes) and click on OK
4) Browse to "Computer Browser"
5) Right click on "Computer Browser" and click on Properties.
6) Change Startup Type to "Automatic"
7) Click on Start.
8) Click on OK
9) Browse to the Symantec Endpoint Protection Manager Services
10) Restart the Symantec Endpoint Protection Manager Services
Login to the Symantec Endpoint Protection Manager and run the Client Deployment Wizard.
If the above steps do not help, work on the steps provided in the Article below:
Symantec Endpoint Protection: Preparing computers that run Windows Vista for remote client deployment