If you want to Specify SEP client group follow below steps
Please Follow the Steps provided below:
1) Open and Login to the Symantec Endpoint Protection Manager
2) Go to 'Clients' and Select the Right group to which the Client belong to / report to.
3) Click on 'Policies' Tab
4) Make sure the check box that says 'Inherit policies and Settings from parent group' is unchecked.
5) Double Click on Antivirus & Antispyware policy [Unshared]
6) Click on Edit shared Button
7) Uncheck on 'File System Auto Protect' or/and Unlock the Lock next to it.
8) Wait for few Seconds and then check the client.
Or Specify SEP client
open registry..start -run - regedit
go to
HKLM\software\symantec \symantec endpoint protection \AV\storages\file system \real time scan
on the right hand side u wil find a key called OnOff..make that value to 0
0 and 1 wil control it....;)