The computer is getting a successful ping response from an Internet public IP address such as 188.8.131.52 but the user is unable to access Internet web pages through a web browser. A DNS poisoning may also occur.
This issue is typically caused by a problem with domain name server (DNS) resolution because the Internet service provider’s DNS servers are unavailable or a problem with the security software (usually a firewall) running on the computer which is attempting to access the Internet.
Computers use DNS servers to allow a user to remember a domain name, such as http://google.com, rather than needing to remember the actual IP address, such as http://184.108.40.206. If a computer is unable to reach a DNS server any application, such as a web browser, using domain names will not work properly. The simplest test of a computers ability to resolve domain names is with the ping command. For more information about using the ping command, please see How to check if a Microsoft Windows PC is online or How to check if a Mac OSX computer is online.
Attempt to ping a domain name like google.com. If properly connecting to the DNS server a result similar to this example will be displayed:
If the computer is unable to resolve the domain name a result similar to the result below will be displayed.
The ability to successfully ping an Internet IP address like 220.127.116.11 but inability not able to resolve domain names like google.com can be resolved by manually assigning DNS servers within the CradlePoint’s router. Click one of the following links for assistance manually assigning DNS server addresses, How to manually assign DNS servers on a Series 1 or 2 CradlePoint or How to manually assign DNS servers on a Series 3 CradlePoint
The ability to successfully ping both IP addresses and domain names while still not being able to access the internet is typically caused by a computer’s security software, usually the firewall. Rebooting the computer can resolve many of these issues. This problem is also often solved by disabling or uninstalling the computer’s firewall software, then re-enabling or reinstalling the software once everything is working again. It may be helpful to contact your computer manufacturer’s technical support for assistance resolving these kinds of software problems.