The key to resolving Vista network connection problem in a wireless home environment is to familiarize yourself with how the network works when you are not experiencing problems. Thus, you would more likely be able to easily identify what is not working if you know how the network should work when you are not experiencing connection problems. In addition, the Vista operating system provides for a diagnostic tool that can guide you as to where the connection problem is and suggests actions that may resolve the problem. You can open your control panel, click on Network and Internet, then click on Network and Sharing Center to view how your computer is connecting to the Internet.
When your network is working normally, you will see three elements on the diagram that is shown on the Network and Sharing window: your computer, the name of your wireless network, and the globe that symbolizes the Internet. You may conceptually remind yourself that the globe essentially represents the network equipments in your Internet service provider. More particularly, your wireless router talks to another router in the premises of your Internet service provider. When nothing is wrong with your wireless home network, the diagram is clean and you don't see any red or yellow symbol that depicts that there is a connection problem. Your wireless network name will also be displayed if you are not experiencing any problem with your Internet connection.
The connection from your computer to your wireless router is an area that is within your control and therefore you can pretty much do whatever is necessary there to resolve your problem. The other half of the connection between your router and your Internet service provider is a shared area that you don't have absolute control of and thus what you can do there is much more limited. In addition, the closer the problem is to your computer, the more serious the problem is, meaning that if the connection between your computer and your wireless router is lost, there is no way that you can connect to the outside world.
Two things must happen for you to be able to access the Internet: your computer must be connected to your wireless router, and your wireless router must be connected to the router in the premises of your Internet service provider. The more common problem that you would be experiencing would be between your wireless router and your Internet service provider's router.
The most common way by which connection is achieved between these two routers is for your wireless router to be able to get valid Internet Protocol (IP) addresses for its use and for use in determining where information packets are to be delivered. Typically, your wireless router asks and receives an IP address that it can use for a specified length of time only and needs to renew the lease before it lapses. This renewal process can take a while to accomplish and you will experience a temporary loss of connection to the Internet. But once the process is complete, connection is quickly re-established.
You can easily find out if such is the case by looking at the log of your wireless router. When you see a series of exchanges between your wireless router's Dynamic Host Configuration Protocol (DHCP) client and the DHCP server of your Internet service provider's router, then a renewal process is happening and you pretty much can't do anything but to wait until the process has been completed. A more common situation is that your wireless router is unable to connect to its Domain Name Service (DNS) server. You can find out if such is the case when you see a red letter X on the line between your wireless router and the globe in the Vista Network and Sharing Center diagram. You can click on the red letter X mark and Vista will inform you that there is something wrong with the DNS operation in your wireless router. This can typically be resolved by opening your router's web interface and renewing the DHCP lease on your router's IP address.
When DHCP is enabled in your wireless router a similar situation can arise when for one reason or another, your computer fails to get a new IP address or fail to renew its IP address from your wireless router. You will know that such is the case when you see a yellow triangle on the line between your computer and your wireless router in the Network and Sharing window of your Vista control panel. Your wireless router will be shown as unidentified and you won't be able to access the Internet at this point. You can click on the yellow triangle to diagnose the problem and one of the actions suggested is to automatically get the required IP addresses from your router. You can click this option to resolve the problem, then wait as the diagram changes to normal as the problem is being solved.
If you want a more technical solution, you can open a command prompt in your Vista computer and run it as an administrator. Type ipconfig /all and check what IP address the wireless adapter of your computer is using. If it belongs to the 169 series of numbers, then your computer automatically assigned that address for itself, failing to find a DHCP server where it can get one that is valid for your network. Enter the ipconfig /renew command and wait for the command's results. You should see that your computer has acquired a valid IP address for your network. Check again your Vista's Network and Sharing Center diagram to confirm that your network is back to its normal operation.
It would be a good idea to wait for a few minutes and let Vista resolve the connection problem by itself before doing any troubleshooting activity. Sometimes, the problem only needs a few more time before being resolved. Try logging off and logging on again or rebooting your Vista computer first and see if the problem goes away. If nothing happens, then it is time to find out where the problem lies and then renew the DHCP lease on your router or on your computer as you determine by looking at the Network and Sharing Center on your Vista control panel.
Read my other article on working quickly while taking care of your Vista computer at: http://publishtoweb.blogspot.com/2011/12/working-quickly-while-taking-care-of.html.
Read my other article on shielding your Vista laptop from attacks with a wireless DLink router at: http://publishtoweb.blogspot.com/2011/06/shield-your-vista-laptop-from-attacks.html.
Read my other article on why microphone is not heard on the speakers of Vista laptop at: http://publishtoweb.blogspot.com/2009/03/why-cant-my-voice-be-heard-on-speakers.html.