User`s manual

Appendix 15. Troubleshooting Internet Security Router User’s Manual
140
Problem Troubleshooting Suggestion
addresses within a predefined pool
PCs cannot display
web pages on the
Internet.
Verify that the DNS server specified on the PCs is correct for
your ISP, as discussed in the item above. You can use the ping
utility, discussed in the following section, to test connectivity with
your ISP’s DNS server.
Configuration Manager Program
You forgot/lost your
Configuration
Manager user ID or
password.
If you have not changed the password from the default, try using
“admin” as both the user ID and password. Otherwise, you can
reset the device to the default configuration by following the
instructions provided in section 12.5.1 “Reset System
Configuration”. WARNING: Resetting the device removes any
custom settings and returns all settings to their default values.
Cannot access the
Configuration
Manager program
from your browser.
Use the ping utility, discussed in the following section, to check
whether your PC can communicate with the Internet Security
Router’s LAN IP address (by default 192.168.1.1). If it cannot,
check the Ethernet cabling.
Verify that you are using Internet Explorer v5.5, Netscape 7.0.2
or later. Support for Javascript® must be enabled in your
browser. Support for Java® may also be required.
Verify that the PC’s IP address is defined as being on the same
subnet as the IP address assigned to the LAN port on the
Internet Security Router.
Changes to
Configuration
Manager are not
being retained.
Be sure to click on button to save any changes.
15.1 Diagnosing Problem using IP Utilities
15.1.1 ping
Ping is a command you can use to check whether your PC can recognize other computers on your network
and the Internet. A ping command sends a message to the computer you specify. If the computer receives the
message, it sends messages in reply. To use it, you must know the IP address of the computer with which you
are trying to communicate.
On Windows-based computers, you can execute a ping command from the Start menu. Click the Start button,
and then click Run. In the Open text box, type a statement such as the following:
ping 192.168.1.1
Click . You can substitute any private IP address on your LAN or a public IP address for an Internet
site, if known.
If the target computer receives the message, a Command Prompt window displays like that shown in Figure
15.1.