Make sure your wireless network adapter's TCP/IP Properties are set to "Obtain an IP address automatically" and "Obtain DNS server address automatically".  You can find these setting by following these steps.

Locate on your desktop's system tray (lower right corner), the double computer icon. Locate the icon that reflects ths wireless connection.  Right click on this icon.

You will see the following window.  Click on the "Properties" button.

Below is the properties window.  Move the elevator on the white window down to the bottom until you find the "Internet Protocol (TCP/IP) item.  Click on it once to highlight (blue background as pictured below). Once highlighted, click on "Properties".

Below are the properties for the Internet Protocol (TCP/IP).  Click on the radio buttons to obtain an IP address automatically and to obtain DNS server address automatically.

Once you have completed this, hit ok and until you have returned back to your main desktop.

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