1. Select menu Security Profile-Application Control, edit the default sensor, and click Add Signature under Application Override.

2. Add a filter, select Name, and enter QQ, and all QQ-related signatures will be filtered out. Select QQ signature, and click Use Selected Signature.

3. The default action of the newly added signature is blocking. Click Apply.

4. Start application control on the Internet access policy of 172.2.3.38 IP address.