Connect to the access point. Wait for it to timeout giving you and IP address.
Open up a "Command Prompt" window.
Type, "ipconfig /release" (no quotes)
Give it five oro ten seconds.
It should show you a list of Adapters (such as your wireless card) and your wireless card's IP should be 0.0.0.0
Type, "ipconfig /renew" (no quotes)
Give it thirty or seconds and see if it gives you a valid IP.

Report back with results.

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