Common Wireless Internet Problems

Here's the situation: your PC reports "Excellent" signal strength to the wireless router, but your PC is unable to connect to the internet.

As usual, to better understand the possible solutions, we must first address the possible problems.

Some background information:

There are actually 3 connections in this scenario:

1. From the PC to the wireless router
2. From the wireless router to the modem (cable or DSL)*
3. From the modem to the internet

* In some cases, the wireless router and the modem have been "combined" and placed in the same box. In this case, you can just assume that the connection between these two is made and has no problems. If the problem is here, you're in trouble!

When the PC reports "Excellent" signal strength, it is simply referring to connection #1. If you just plugged the wireless router into power, and nothing else, and turned your computer on, it would report "Excellent" signal strength. The PC simply assumes (and we know what that makes it) that if it can connect to the wireless router, then it can connect to the internet. But wait, it is assuming that there are two more connections present and working!

Usually, in this situation, the problem is simply the wireless router and the modem are out of sync. Here's why:

Situation #1:

Every computer in the world on the internet has to have an IP address. It's like a house address for mail delivery. If you don't have an address, you can't get on the internet.* (* This isn't 100% true, but for the purposes of this article, it is.)

The wireless router is in charge of getting the address from your Internet Service Provider (ISP). Well, we could quickly run out of addresses if we just handed them out and they had to be valid forever, so we give them a "lifetime". Usually this is about 1 day. So, every 1 day, the wireless router will talk to the ISP and say, "Hey, my IP address expired. Can I have another one?" At this point, the ISP will say, "Sure, here it is."

Now, to keep things "simple", the ISP will normally give you the same address over and over and over. BUT, if they did that, you could take advantage of that and setup servers and do other things that the ISP doesn't really want you to do because it uses the connection pretty heavily.

This is precisely where the problem comes in. Somehow the wireless router gets out of sync with the ISP. At this point, the wireless router continues to try to use the old IP address and the ISP won't accept it because it just handed out the new IP address and expired the old IP address.

So, your PC is connected to the wireless router with "Excellent" signal strength; the wireless router is connected to the modem; and the modem is connected to the internet -- but the last two connections aren't valid because the wireless router and the ISP are out of sync.

Solution:

1. Unplug the wireless router from the power.
2. Unplug the modem from the power.
3. Count to 30 (60 if you have the time and patience).
4. Plug the modem back into the power.
5. Count to 30 (60 if you have the time and patience).
6. Plug in the wireless router into the power.
7. Wait for your PC to reconnect to the wireless router.

** Also see "Notes for Steps 4 & 5" below!

Situation #2:

Your computer is reporting "limited or no connectivity".

Your computer was unable to get an IP address from the wireless router. (It probably has an AutoIP address of 169.254.xxx.yyy which isn't much good in our situation.)

Possible Problems:

1. The "key" that was entered to connect to the wireless router was input incorrectly.
2. The wireless router has "MAC address filtering" enabled, and your computer isn't on the approved list.
3. The wireless router is out of IP addresses to give out (this isn't very likely).

Again, let's try to understand the process a bit better. When a PC connects to a wireless router, it goes through a few steps:

1. The PC "associates" with the wireless address. This is basically when the PC says "Okay, wireless router, I'm choosing you to connect to, so when I say things, you need to pay attention!"
2. Once this "association" takes place, the PC then tells you that the connection has been made and the signal strength as "Excellent".
3. It then does all the crazy encryption and "key" stuff to encrypt the connection.
4. *It then asks the wireless router for an IP address.
5. *If it cannot get an address, it will notify you that the connection has "limited or no connectivity."

Notes for Steps 4 & 5:

Very seldom you will come across a situation where the IP address has been set manually on your computer. This means that every time your computer connects to the wireless router, it will use the same IP address. This is a bit more technical and requires a small bit of technical know-how, but it's do-able. IF THIS IS THE CASE: then it will skip steps 4 & 5 and just try to use that IP address. If that IP address isn't one of the IP addresses that the wireless router can communicate with, then the PC and the wireless router simply just won't be able to talk to each other. At this point, the computer will not list the connection as having "limited or no connectivity", it simply won't work.