Originally posted by F1man
I just sent it to a computer professional.... See what they can do. 
OK, you need to think about these things logically. Your internet connection is only a means of getting from A to B. You go through various stages on the way, and you therefore just need to test how far you can get. Once you do that, you can establish where in the chain the failure lies.
So...
In the above example (no connectivity), you should do the following:
1. Test more than one web site. Test "high availability" sites, like
www.microsoft.com, and
www.cnn.com. Then test your ISP's home page. If you can't hit any sites, then it means that at the very least you have a problem with web or DNS (Domain Name System) traffic.
2. Check to see what your IP address is. Click Start > Run, and type in "ipconfig /all". You'll see something like this:
Code:
Windows 2000 IP Configuration
Host Name . . . . . . . . . . . . : 00305A
Primary DNS Suffix . . . . . . . :
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
Ethernet adapter WLAN:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : U.S. Robotics 22Mbps Wireless Cardbus Adapter
Physical Address. . . . . . . . . : 00-C0-49-B0-6E-D6
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
IP Address. . . . . . . . . . . . : 192.168.1.102
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.254
DHCP Server . . . . . . . . . . . : 192.168.1.254
DNS Servers . . . . . . . . . . . : 195.110.64.205
158.234.8.70
Primary WINS Server . . . . . . . : 213.86.115.34
Lease Obtained. . . . . . . . . . : 02 February 2004 19:18:32
Lease Expires . . . . . . . . . . : 03 February 2004 19:18:32
Ethernet adapter LAN:
Media State . . . . . . . . . . . : Cable Disconnected
Description . . . . . . . . . . . : 3Com 10/100 Mini PCI Ethernet Adapter
Physical Address. . . . . . . . . : 00-00-86-44-C2-00
Since you're using a router, you should expect to see an IP address in the range of 192.168.1.x. You should look for the line
DHCP Server, and you should see the address set to the same as your
Default Gateway, and it should be the same as the address you're expecting your router to be on (since a
router acts as a
gateway by
routing signals between your local area network (LAN) and the internet).
One thing to watch out for is that the line
IP Address says exactly that, and does not say
IP Autoconfiguration Address. If it says Autoconfiguration, the PC did not pick up the DHCP Server, which means that the computer failed to communicate with the router. (Power cycle the router, then the PC, and check cabling if the problem persists).
If you have an IP address, (as opposed to an autoconfiguration address), then you should
ping the router, by typing "ping 192.168.1.254" (substitute your router's address). You should get:
Code:
Pinging 192.168.1.254 with 32 bytes of data:
Reply from 192.168.1.254: bytes=32 time<10ms TTL=150
Reply from 192.168.1.254: bytes=32 time=10ms TTL=150
Reply from 192.168.1.254: bytes=32 time<10ms TTL=150
Reply from 192.168.1.254: bytes=32 time<10ms TTL=150
Ping statistics for 192.168.1.254:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 10ms, Average = 2ms
If you get "Request Timed Out", you have no connection to the router.
3. If your PC is connecting to the router, but cannot connect to the internet, you should try another PC on the network. Repeat the above tests, and if you get the same results, then your PCs are connecting to the router, but the router is not connecting to the internet. Log in to your router's web interface, and command the router to renew its DHCP lease. It should do so. If it does not (or if you cannot do this manually), reset your connection to the internet by power cycling your modem. We'll do another test, prior to calling your ISP.
4. Perform a traceroute to an internet host. This is where you ping an internet host, but test the route between you and the host. It goes something like this:
Code:
C:\>tracert -d ftp.novell.com
Tracing route to thelev.provo.novell.com [130.57.1.22]
over a maximum of 30 hops:
1 10 ms 20 ms 11 ms 10.124.0.1
2 10 ms 20 ms 10 ms 62.31.64.33
3 30 ms 20 ms 61 ms 194.117.136.142
4 20 ms 30 ms 20 ms 166.63.222.37
5 101 ms 100 ms 100 ms 206.24.226.100
6 100 ms 100 ms 101 ms 192.205.32.45
7 100 ms 110 ms 100 ms 12.123.9.86
8 100 ms 100 ms 100 ms 12.122.10.53
9 101 ms 110 ms 100 ms 12.122.9.129
10 120 ms 120 ms 121 ms 12.122.10.2
11 170 ms 160 ms 171 ms 12.122.10.118
12 160 ms 170 ms 161 ms 12.122.5.33
13 170 ms 160 ms 160 ms 12.122.2.237
14 160 ms 170 ms 170 ms 12.127.106.34
15 180 ms 180 ms 170 ms 192.94.118.220
16 180 ms 170 ms 180 ms 130.57.1.22
Trace complete.
Note that the step to my router (192.168.1.254) is skipped. This is normal unless you're part of a massive corporate network. You don't particularly need to pay attention to the addresses that come up, although if the trace fails (you get a set of "* * * *" lines), your ISP may want to know where the trace failed. Oh, and on the command itself, you can always use the host "ftp.novell.com", and the "-d" switch prevents the computer from doing DNS lookups, which speeds the process.
So now you've assessed where the connections failed, you should know enough to know where the problem lies. Make the appropriate calls. Always look to replace the bits that are easiest. Use the good computer to download the latest driver for your network card. Try a new network cable, that sort of thing. Store "experts" will just charge you a fortune for something you can do in an hour or so for a few dollars. And the number of horror stories I've heard about "experts" increasing the scope of the problem doesn't bear mentioning here.
Anyways, Friday nite I was about to go and upload some photos for my mom when a bloody Page Cannot be displayed error came up. And I cant get online. Nearly ALL DAY today from 11:30 to 9:45 (which is right now) I have tried to get it running again. I did the following:
)
