There are actually several things that could be causing your problems, so without knowing exactly how you're currently configure, it's going to require a bit of "tweaking" and testing on your end.
First, if your router is set to DHCP (which is what allows the router to assign an IP address to each machine that wants to access the Internet through it), then you need to also make sure that your computer is not set to a specified IP address. Do this by going to the control panel, then to network connections, then to properties. Finally, there is a listing of things like Client for Microsoft Networks, QoS Packet Scheduler, and Internet Protocol....click on Internet Protocol and then click OK. In the next popup window, make sure that the item for "Obtain IP address automatically" is selected.
You can also specify the network that your computer should automatically connect too, but that setting process varies depending on the operating system of your PC (Windows 7, XP, 98, 95, etc), so without knowing what you're running, that's a bit tricky here.
However if your IP DHCP settings are ok, then the next step is to look at the security settings of your router, which again can be very different depending on model and make, so I'll have to be a bit vague here.
Check your router setup to make sure the following settings, so you may have to "hunt & peck" around in the router settings to verify these things:
1. Is the router set to DHCP? If not, do that for ease of operation. If you want to specify your IP addresses (which has a very specific purpose), then let me know and we can go down that road)
2. Check your security settings, and make sure that there isn't some sort of password or high level of encryption that's preventing the connection. I personally prefer the default settings for almost every occassion...it just makes things easy.
3. There's also an area where you can set the number of computers (called the range) that are allowed to connect to the router at any one time. This is generally on the first page of the settings, and should be set to 254 if you want to just make it easy for anyone to connect to the network, or just set it to the number of computers you have, or maybe 1 more than the number of your computers so that friends who come over with a laptop can also get online (if that's a case for you).
4. Last, if it's a DLink or Lynksys router and you are just completely stumped, try their live support. It's free, and although they are all based in China or some foreign place, and are hard to understand sometimes, they are actually very good at resolving issues like yours, and can even remotely connect to your computer and router to verify settings for you.
I hope all this helps! Good luck!
Rob
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