Overclock.net - An Overclocking Community - View Single Post - A guide to the interworkings of the internet
View Single Post
post #8 of (permalink) Old 11-29-2009, 11:27 PM - Thread Starter
Retired Staff
Lige's Avatar
Join Date: Jan 2008
Posts: 8,048
Rep: 391 (Unique: 283)
Things to consider when you have Internet Problems

Taken from this thread with procpuarie's permission.


  • Have you connected the modem straight to your computer?
  • Do you have DSL line filters connected to all your phones running on the same phone line?
  • Is the telephone cable connecting your DSL modem to your phone jack less then six (6) feet long? Does it have any bare wires or damage?
  • How far away are you from your central office (click here)? Is it more then four (4) kilometers (2.5 miles)?
  • Do you live in an older area (older homes/telephone infrastructure)?
  • Is the telephone wiring poor in your house?

  • Have you connected the modem straight to your computer?
  • Is your modem connected to a coax splitter or smiler device?
  • Do you have a coax filter connected to your modem (or any line your modem runs through)?
  • Is the coax cable connected to your modem free of any bare wires or damage?
  • Is the modem of the correct version of DOCSIS for your line speed?
  • Is the coax wiring poor in your house?

Solutions to Common Problems

Internet Connectivity

  • Problem: You recently hooked up a router or new computer to your modem and your internet browser does not load pages.
Answer: Have you tried power-cycling your modem? Unplug the modem for thirty seconds, after thirty seconds plug it back in, depending on if you are running windows XP or Windows Vista/7 click Repair or Diagnose. Alternative you can use the cmd command:
ipconfig /releaseipconfig /renew
Or restart the computer.
  • Problem: You can currently connect to AIM, Skype, IRC, however you can not connect to websites.
Answer: There are several resolutions to this. You can reset the cable modem hoping that this attempts to fix the problem. You can reset the TCP/IP stack in Windows XP/Vista/7 using this command:
Windows XP:
This command allows you to output all actions to a log that will be saved on the C:\\ drive.
netsh int ip reset c:\
esetlog.txtnetsh winsock reset catalog
You could also use the program located here.
Windows Vista/7:
netsh winsock reset (make sure you are elevated or have disabled UAC)
For more information about the Windows netsh command, please read up on it here.
If you have done all the following, or if you can use another internet source such as a school, a neighbor (with their permission), etc, then it is most likely your ISP and something on their end. The only thing you can do in that instance is wait. The website/server could be down and not loading for anyone. If that is the case, I would try this site: http://downforeveryoneorjustme.com/.
  • Problem: Your game can not connect to a server, or you are having a hard time getting a game or application to work with the internet.
Answer: You may need to set up port forwarding for the specific application. Portforward.com has the most complete guides for games and applications and video game consoles. It is very easy, first choose your routers brand/model, and then wait or click through the advertisement, then select the program, game, or video game console you want to setup and then follow their guide.
As far as I am aware, they do not provide support for third-party firmware such as, DD-WRT, Tomato, pfsense, untangled, etc.
Networking Connectivity
  • Problem: You are trying to turn your Wireless Home Router into a Wireless Access Point to extend range. Whatever reason though, you are having issues setting it up.

    Most home routers can normally be set up as limited, or complete Wireless Access Points. How do you do this you ask? Look below. Thanks to Enterprise for his picture
    1. Log into your router using it's IP address. You can accomplish this by going to your browser. Finding the URL Bar, and inputting it there.
    2. You will then be prompted for a username and password. These differ for each firmware, and model/manufacturer of router. So read the manual for instructions in this case.
    3. You will be prompted with this screen (Looks similar in almost all instances for Linksys routers)
    4. You should see Internet Connection Type for most routers, this should either be left as is or set to disabled if that is an option.
    5. For the Local IP Address, change it to something outside of the DHCP Range of your current router. So, if Router 1 has a DHCP Range of 50 Addresses, and it starts at any IP range from to will work.
    6. Now, go to the Security Tab and disable the Firewall so that it has the following items disabled:
      Thank you coldrush for the below picture.
    7. Now, finally go into your NAT/QoS tab. You will need to disable any port forwarding, UPnP, or Quality Of Service you have set up.
    8. Now, go to the Wireless tab. And put the SSID that you want to repeat.
      So, for example, say Router 1's Wireless SSID is ABCDEFG, and you want to extend it's range on Router 2. Go to the Wireless tab on Router 2 and use the Wireless SSID as ABCDEFG. Make sure that you don't use the same Wireless Channel, on both routers, or there will be errors/issues with being able to connect. Preferably, you always want to use channels seperate from each other, so, Router 1 is broadcasting on Channel 1, you would preferably want Router 2 to broadcast on Channel 11. If you have three or more routers, you would want to rotate the channel broadcasting, Router 1 broadcasting on channel 1, Router 2 broadcasting on channel 6, Router 3 broadcasting on channel 11, Router 4 broadcasting on Channel 1, and so on.

    Third-party firmware, such as DD-WRT, or Tomato, have guides already written out on how to accomplish this. Listed here (DD-WRT) is a decent one already written on how to configure a DD-WRT enabled router to become a Wireless Access Point.

Mr. Nude_Lewd_Man's troubleshooting guide for xDSL and Virgin Media (as attached in a post below)

How to troubleshoot Internet Connection Issues with xDSL

Written by: Nude_Lewd_Man, 16 Dec 09

Description of why you would be performing this task:

A user can’t access the internet.

Procedures and steps

1. Check what type of connection the user has to their ‘router’. Most of the following relate to modem/router/firewall/switch combination devices, and although most can also be replicated for other xDSL connections, those who use Virgin Media (formerly NTL or Telewest) or 3G USB dongles have different steps.

2. Ask the user to PING the router. Get them to go Start > Run > type “cmd” > [Enter] > type “ipconfig” > [Enter] > note the “Gateway” address > type “PING <router IP>” [Enter]. Also ask them to PING an external IP – you can ping a site from your computer and give them the IP for them to “PING <IP>” [Enter]…

3. While they’re doing this, try to connect onto their computer, if you can connect then it is likely to be a DNS issue. It is also advisable to check whether they are connected by wirelessly or with an ethernet/network cable.

4. If you can’t connect, ask them to go to the router. Get them to tell you which lights are flashing, and what colour the lights are. Bear in mind that normally only one of the <number> lights will blink (in orange on ZyXELs) per computer that has an active wired connection.

5. If there is no blinking LED for the internet light, ask them to turn the router off, wait 10 seconds and power it back up again. This normally takes around 1-3 minutes to get back to full operational state. (For USB xDSL modems, get the user to remove the USB cable from their computer for 10 seconds)

6. Ask them to keep you updated with which lights are flashing; you mainly want to know about the DSL/Internet LED. This is likely to flicker up green at first, if it goes orange this points towards there being an issue.

7. A lot of, but not all, users should have a (analogue) handset in their location, as them to pick this up and let you know whether there is a dial tone. It is a good idea to get the user to confirm that there is a ‘ADSL Filter’ in place: there needs to be on between each wall (phone) socket and any telecommunication device – voicemail, Sky (TV) boxes can all count, as do some ‘monitored’ alarms.

8. If there isn’t a dial tone, or if the line has a lot of noise/crackle, then this points to an issue with the line. If there is a tone but it is noisy, check whether there is a spare filter and ask them to swap this with the one currently in use, then try the line again.

9. If there isn’t a dial tone, or if the line is still noisy/crackly after changing the filter, this needs to be taken up with BT. Check
www.bt.com for contact details, and get in touch. If there is no dial tone, this could be that the bill hasn’t been paid or that there is an infrastructure fault – the latter needs to be dealt with by BT OpenReach.

10. If there is no (unusual) noise, you can test how far the connection can get by using some special credentials, but this would need to be done on site (unless they have access into the router’s configuration pages). These credentials follow. Ensure you have the user take down their Login Name (paste into Notepad/etc) before getting them to change it in the router.

Google Spreadsheet

The credentials above can only access a VERY limited number of pages, which are listed here:
www.bt.net/digitaldemo (
http://speedtester.bt.net (

As a brief explanation of the above see the image below:

How to troubleshoot Internet Connection Issues with Virgin Media

Written by: Nude_Lewd_Man, 16 Dec 09

Description of why you would be performing this task:

A user can’t access the internet.

Procedures and steps

Virgin doesn’t use xDSL, but can provide digital television through their single cable to the property. The internet will/can also be carried through this same cable; connection is made by the cable modem to the Virgin Media servers/network directly and there is no password on the internet account.
  1. As in step 2 above, get the user to ensure that they have a (valid) IP address, and get them to PING their gateway IP address. Again, it is a good idea to give them the IP of an internet site (that allows PING replies) to test the connection.
  2. Below is an image of a Virgin Cable Modem. It should have the “power”, “enet”, “sync” and “ready” lights on. If any of these lights aren’t on, then this will need to be restarted. If the user has this and also a firewall/switch/WAP between their computer and the cable modem, then this normally/often needs to be restarted too. If they connect their computer directly to this box, then disconnect the network cable.
  3. If it does need to be restarted, then power down the cable modem and any firewall/switch device connected to it. After about 30 seconds, they can restart the cable modem.
  4. While the cable modem is starting up, the lights will flicker and go off. Once the “sync” light has stabilised (to permanently on) and then the “ready” light has done the same, the user should then start any other device/s that were powered down, before finally restarting/reconnecting any other computers/devices. (The reason for this is that (in the past at least) Virgin/NTL/Telewest used to ‘lock down’ their connections to the MAC address of the first device after the cable modem.)
  5. If the “sync” and/or “ready” light don’t go on, or aren’t constant, then the user will need to get in touch with Virgin Media. They should be able to dial 150 (from their Virgin Media telephone), otherwise their contact details should be found on their website http://www.virginmedia.com/

Lige is offline