Symantec NIS2005 Manuel D’Utilisation

Frequently asked questions
Troubleshoot security protection

60

To allow the use of your local network, including file and 
printer sharing, place the computers on your local 
network in the Trusted Zone.

Why can’t I connect to the Internet via my cable 
modem?

If your network accesses the Internet via a cable 
connection, you may need to make your computer’s 
NetBIOS name visible. While the NetBIOS name is 
visible, the files and folders on your computer remain 
hidden.

To make your NetBIOS name visible

1

In the main window, double-click 

Personal Firewall.

2 In the Personal Firewall window, on the Advanced 

tab, click 

General.

3 In the General Rules dialog box, click 

Inbound NetBIOS Name.

4 Click 

Modify.

5 In the Modify Rule dialog box, on the Action tab, click 

Permit.

6 Click 

OK.

7 In the General Rules dialog box, click 

OK.

8 In the Personal Firewall window, click 

OK.

Some Internet service providers scan the ports on users’ 
computers to ensure that they are keeping to their 
service agreements. Intrusion Detection might interpret 
this as a malicious port scan and stop communications 
with your cable system. If this occurs, you need to let 
your cable provider run port scans.

To allow ISP port scans

1

In the main window, double-click 

Detection.

2 In the Intrusion Detection window, on the AutoBlock 

tab, click 

Exclusions.

3 In the Exclusions dialog box, select the IP address 

your ISP uses for port scans.
Your ISP can provide this information.

NIS2005.book  Page 60  Sunday, August 1, 2004  3:24 PM