When you attempt to view a Web page in Internet Explorer using a cable modem, you may be unable to do so or you may receive the following error message:

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This behavior can occur if your cable modem is configured to automatically obtain an IP address from a Dynamic Host Configuration Protocol (DHCP) server. Windows XP automatically assigns an IP address if your adapter is unable to obtain one. Because a connection across a cable modem is slower than a connection across a network, using Autoconfiguration, Windows may automatically assign an IP address before the cable modem is able to obtain one from the DHCP server. Since this automatically assigned IP address is not valid for the Internet service provider (ISP), you can not access resources on the Internet using the cable modem.

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To work around this issue, use the appropriate method:

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One-Way Cable Modems

1.	Click Start, and then click Run.
2.	Type cmd, then press ENTER.
3.	Type ipconfig, then press ENTER.
4.	Note the PPP Adapter in the list of adapters.
5.	Verify that the PPP Adapter in the list of adapters has a Windows assigned IP address. If Windows has automatically assigned an IP address before the cable modem is able to obtain one from the DHCP server, then the IP address for the PPP Adapter will have the following address: 169.254.x.x. where x is any number between 0 and 255.
6.	Verify that the network adapter connected to your cable modem in the list of adapters has a Windows assigned IP address. If Windows has automatically assigned an IP address before the cable modem is able to obtain one from the DHCP server, then the IP address for the network adapter will have the following address: 169.254.x.x. where x is any number between 0 and 255.
7.	Type ipconfig /release, then press ENTER. The IP addresses should be both be 0.0.0.0.
8.	Type ipconfig /renew, then press ENTER. The DHCP server should now provide the correct IP address.

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Two-Way Cable Modems

1.	Click Start, and then click Run.
2.	Type cmd, then press ENTER.
3.	Type ipconfig, then press ENTER.
4.	Verify that the network adapter connected to your cable modem in the list of adapters has a Windows assigned IP address. If Windows has automatically assigned an IP address before the cable modem is able to obtain one from the DHCP server, then the IP address for the network adapter will have the following address: 169.254.x.x. where x is any number between 0 and 255.
5.	Type ipconfig /release, then press ENTER. The IP address should be 0.0.0.0.
6.	Type ipconfig /renew, then press ENTER. The DHCP server should now provide the correct IP address.

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There are two types of cable modem services, one-way cable modems and two- way cable modems. One-way cable modems send information over the phone line, and receive information over the cable. Two-way cable modems send and receive information over the cable.

When Windows does not initially detect a DHCP service, it assigns an IP Autoconfiguration Address (APIPA). If Windows later detects a DHCP service on the network, Windows switches from the IP Autoconfiguration Address to the address that is assigned by the DHCP server.

To disable Autoconfiguration either on the entire computer or on a per-interface basis, you need to modify the registry. For additional information, click the article number below to view the article in the Microsoft Knowledge Base: For additional informationabout troubleshooting cable modems and IP configuration, click the article numbers below to view the articles in the Microsoft Knowledge Base:

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