Troubleshooting Wireless Networks
If you're having trouble with a wireless network here are a few tips that might help smooth things out...
You've probably tried rebooting the computer but have you tried rebooting your wireless access point? Just pull the power plug, count to 5, plug it back in.
Is This Thing On?
Most portable computers have a button or switch that turns the wireless radio on/off. It may be a combination of the Function Key and an "F" key (like "Function + F2") on your keyboard or it might be a physical button or switch somewhere else on the machine. Check it to make sure that your WiFi is actually turned on.
Make sure that you have the latest drivers installed for your wireless adapter and that you have the latest firmware installed for your wireless access point. Especially if you recently upgraded a machine from Windows Vista to Windows 7 you may not have the current wireless adapter drivers installed.
There are a couple of kinds of interference that are relevent with wireless networks. One is SSID interference. The SSID is the "name" of the wireless network - it's what you see when you look at the list of available networks. If your network has the same SSID as another network in range that can cause some issues such as poor performance or even random disconnects. Change the SSID on your network to have a unique name.
Another kind of interference can be frequency interference. A lot of wireless networks operate on the 2.4Ghz frequency. Unfortunately so do most microwave ovens. If your computer or router is near a microwave oven you may want to move it.
What level of security do you have configured on the access point? WEP? WPA? WPA2? Something else? Make sure your wireless device supports that level of security, first of all. Nearly all modern devices support at least WPA. Most support WPA2.
Do you have the right pass phrase for connecting to the access point? Keep in mind they're almost always case sensitive - so make sure your CAPS LOCK key isn't on, unless the pass phrase is in all CAPS.
If matching the security type and passphrase doesn't solve the problem try turning the security off, temporarily, as a test. If you can successfully connect then, that tells you the security is a factor. Carefully reenable it, paying close attention to the type of security and the passphrase used.
You might try using a gentler form of security, at least at first. If you were using WPA2, maybe try using WPA.
NOTE: WEP is not really security as it is readily cracked.
It may be that your computer is just too far away from your router to get a good signal. If that's the case, and you can't move the computer or the router, try using a range extender. Hawking Technologies makes one that we recommend. You place it roughly halfway between your computer and router, plug it in and configure it to connect to the wireless network. It will broadcast a signal on a new SSID that you can connect to with your computer. You don't have to be using a Hawking router to use the Hawking range extender - it works with any vendor's product. We also recommend the NetGear RangeMax WNR3500 if you're looking for a new wireless router.