|You can't access the internet with a wireless network adapter when you first get the computer unless whatever you are trying to connect to wirelessly to access the internet has no security enabled - no required encryption key or password.|
On some laptops, the wireless adapter may switch itself off if it can't connect to anything.
Also, you have to search for available nearby wireless networks, and choose to Connect to one. If that connection says Security Enabled, you must supply it's encryption code or password, in order to connect to it.
When you get a new wireless router, the wireless broadcast is usually switched off - it must be switched on in the router's configuration.
You can only connect to one wireless device at a time to connect to the internet, e.g. your own router, which may have security enabled for wireless, if you were connecting to it wirelessly previously , or to another router, which may or may not have security enabled for wireless (e.g. it would probably not be enabled at an internet cafe).
Once you have entered the correct code or password for a particular device you connect to, Windows will retain that, but you still need to click on Connect when you change which wireless device you're connecting to, whether that connection requires a code or password or not. .
When you change a setting for a wireless adapter, you may need to restart the computer in order for the setting to take effect.
How do you search for available nearby wireless networks ?
I haven't installed Windows 7 yet, but I have installed Vista and many things in it are the same. However, I do not have a wireless network adapter on that computer.
Look in Help and Support
Search for :
View and connect to available wireless networks.