ZyXEL Communications NBG420N User Manual
Page 267
Chapter 26 Troubleshooting
NBG420N User’s Guide
267
2 Check the hardware connections, and make sure the LEDs are behaving as expected. See
the Quick Start Guide.
3 Make sure your Internet browser does not block pop-up windows and has JavaScripts
.
4 Make sure your computer is in the same subnet as the NBG420N. (If you know that there
are routers between your computer and the NBG420N, skip this step.)
• If there is a DHCP server on your network, make sure your computer is using a
dynamic IP address. See
Section 7.3 on page 102
.
• If there is no DHCP server on your network, make sure your computer’s IP address is
in the same subnet as the NBG420N. See
Section 7.3 on page 102
.
5 Reset the device to its factory defaults, and try to access the NBG420N with the default
IP address. See
Section 7.3 on page 102
.
6 If the problem continues, contact the network administrator or vendor, or try one of the
advanced suggestions.
Advanced Suggestions
• Try to access the NBG420N using another service, such as Telnet. If you can access the
NBG420N, check the remote management settings and firewall rules to find out why the
NBG420N does not respond to HTTP.
• If your computer is connected to the WAN port or is connected wirelessly, use a computer
that is connected to a LAN/ETHERNET port.
V
I can see the Login screen, but I cannot log in to the NBG420N.
1 Make sure you have entered the password correctly. The default password is 1234. This
field is case-sensitive, so make sure [Caps Lock] is not on.
2 You cannot log in to the web configurator while someone is using Telnet to access the
NBG420N. Log out of the NBG420N in the other session, or ask the person who is
logged in to log out.
3 Disconnect and re-connect the power adaptor or cord to the NBG420N.
4 If this does not work, you have to reset the device to its factory defaults. See
V
I cannot Telnet to the NBG420N.
See the troubleshooting suggestions for
I cannot see or access the Login screen in the web
Ignore the suggestions about your browser.
V
I cannot use FTP to upload / download the configuration file. / I cannot use
FTP to upload new firmware.