Check for the following steps
1. Go Centrallized Exception in the Symantecn Endpoint Protection Manager
2. Add or Edit the Policy Centrallized Exception Policy
3. Go to Centralized Exception Tab on the Left Side
4. Click on Add and select Security Risk Exception > Known Risk
5. Select Tracking Cookie and Click OK (Selected Risk Exception will be displayed in the Exception List)
6. Click OK again to close the Policy