Hello,
To Stop and Start the service of the Antivirus package you have to use the command NET STOP service. eg NET STOP "Norton Antivirus Client".This will stop the service and similarly you can Start the service using the NET START service.
You have to create a batch file,with the script having the Net START\STOP service commands.To run the batch file refer the following technotes:
http://seer.support.veritas.com/docs/253162.htm
http://seer.support.veritas.com/docs/259941.htm
Hope this helps you.
Regards
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