Q: What can I do when I cannot connect to a wired or wireless router in Windows Vista?

A: If the router was accessible with Windows® XP, and you are unable to connect with Windows Vista™, try the steps below.

Note: You may not see all of the options listed, depending on which network adapter you have.

1. From the Windows Vista Start menu, click Network.
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2. In the Network window, click Network and Sharing Center.
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3. In the Network and Sharing Center window, click Manage network connections.
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4. In the Network Connections window, right-click the network connection you are trying to use (Wireless or Local Area Connection), and then click Properties.
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5. In the Properties dialog box, on the Networking tab, in the This connection uses the following items area, click to clear check mark from Internet Protocol Version 6 (TCP/IPv6). Click OK.
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6. Try to access the Internet. If you are still unable to connect, continue to step 7.

7. In the Network Connections window, right-click the network connection you are trying to use (Wireless or Local Area Connection), and then click Properties.
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8. In the Properties dialog box, on the Networking tab, click to select your network connection, and then click Configure.
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9. In the Controller Properties window, click the Advanced tab.
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10. On the Advanced tab, in the Property area, for each item with an option of (IPv4), click to select the item, and then change its value to Disabled. After all (IPv4) items have been disabled, click OK. The usual items to look for are: IPv4 Checksum Offload, TCP Checksum Offload (IPv4), UDP Checksum Offload (IPv4).
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11. Shut down Windows, restart the computer, and then try connecting to the Internet.