Useful Information and Resources

Hi everyone!

Welcome to the Networking Help Forums. Please use this forum to troubleshoot any networking problems that you may be having, including problems with routers, switches, small networks, and file sharing.

This sticky contains the following posts:

• Network troubleshooting guide
• Solution to "Access is Denied" error message
• How to post your IP configuation details
• Useful network resources
• Useful network diagrams

Update: This thread is now open so that anyone can post useful networking information for others to read. If you've got something that you think others would benefit from, please post it in this thread (but please remember that this thread is not the location for posting questions - create a new thread for this instead).

If you've got a question to ask, please note that there are other forums in the System Administration section which may be more appropiate for your question: Mail Server Help, Apache Development, Security Policies, DNS, IIS.

Please post sensibly and kindly, and help keep the Networking Help Forums useful for everyone.

Thanks for coming to this section of Dev Shed. I hope that you will return and any questions you have are answered.

Please direct all questions about this forum to me via private messaging.

Thank you,
Edwin

Before posting a problem in the Networking Help forum, please use this checklist to eliminate common problems, to prevent you posting unnecessarily:

• Check that the TCP/IP network protocol is installed on all computers and that it is configured correctly. If you are using DHCP, make sure that an IP address has been correctly assigned to the computer. If you are manually assigning the IP addresses, make sure that they are set correctly. For example, set the IP addresses on the 192.168.0.x subnet, and make sure that the subnet mask is set to 255.255.255.0.
  
  
• Check that the computers are on the same workgroup.
  
  
• Check if you can ping from one computer to the other.
  
  
• Check that the wires are correctly connected, and any wireless devices are in range.
  
  
• Check for firewall software. This needs to be disabled or configured for home networking. Also, if you are using Windows XP, check that Internet Connection Firewall is not enabled on the network connection.
  
  
• If you are using Windows 2000 or XP, make sure that the Guest account is enabled.
  
  
• Try running the Windows XP Network Setup Wizard (if you have Windows XP). This may help solve your problems.
  
  
• If you have trouble browsing the Internet, check if you have a DNS problem. Your computer needs a DNS server to translate a domain name to an IP address. Try browsing to the site http://66.102.9.104. If you can access this site, but can't browse to www.google.com, then you do have a DNS problem. You need to look on your ISPs website for the addresses of their two DNS servers, and then you need to put these into the settings of your local network connection. On Windows 2000/XP, you can open the Network Connections section from the Control Panel and right-click your network connection. Select Properties then double-click Internet Protocol TCP/IP. You should then see two boxes where you can enter the IP addresses of the DNS servers. On Windows 98/Me the process is pretty similar, although you need to find a section named Network in the Control Panel.

If you can't solve your problem working through the checklist above, then feel free to create a new post within the Networking Help forum. Please post as much information as possible, as the more information experts have, the more easily they can answer your questions. You may also find that posting IP configuration details help to solve your problem more quickly (see below for details).

Please read the post at the bottom of this thread (located here) before following any of the advice in this post.

_____________________________

If you have having a problem with an "Access Denied" error message while trying to access shared files/folders, the following information may help.

This was originally posted AWeenieMan.



This was originally posted by jereyeeha80.



This was originally posted by PilotTech.

If you would like to post IP configuration details with your post to help troubleshoot your network problem, please follow the steps listed below, depending on your operating system.

Windows 2000/XP:

Click Start, Run and type cmd. In the black Command Prompt that opens, type:
ipconfig /all > C:\ipconfig.txt
Close the Command Prompt then browse to the C drive on your computer. Find the file named ipconfig.txt, open it, and copy the contents into your post.

Windows 98/Me:

Click Start, Programs, MS-DOS Prompt. In the black MS-DOS Prompt that opens, type:
ipconfig /all > C:\ipconfig.txt
Close the MS-DOS Prompt then browse to the C drive on your computer. Find the file named ipconfig.txt, open it, and copy the contents into your post.

A useful site for finding out about more advanced technologies involved in networking:
http://labmice.techtarget.com/

About.com site giving information on wireless networking:
http://compnetworking.about.com/

About.com site giving information about the Internet and network security:
http://netsecurity.about.com/

Guides on setting up your own home network:
http://www.homenethelp.com/

Microsoft's site showing how Windows XP can easily be used in a home network:
http://www.microsoft.com/windowsxp/...net/default.asp

A site giving detailed information on how to configure port forwarding on lots of different routers.
http://www.portforward.com/routers.htm

Two sites giving details about setting up a network bridge in Windows XP:
http://www.microsoft.com/windowsxp/..._02april22.mspx
http://www.windowsnetworking.com/ar...s/wxpbrdge.html

There are lots of resources on the Internet that help you with networking. If you've found one which you think is particularly useful, please let me know via private messaging and I should be able to add it to the list.

If you are having trouble setting up your first network, and don't know what to plug where, then the following diagrams may help you.

1. wireless_router.jpg
This diagram shows you how you would use a wireless router to connect both a wired and wireless computer together, sharing the Internet.

2. wireless_access_point.jpg
Similar to diagram one, this shows you how you would setup a wired and wireless network using a standard router with an additional access point.

3. crossover_network.jpg
This shows you how to connect two computers directly (without the use of a hub or switch) to share the Internet and files.

4. switch_network.jpg
This diagram shows the connection of three computers to a hub/switch with one computer acting as the Internet host, sharing out the Internet to the other computers.

If you would like any other diagrams here, then please contact me via private messaging.

Please read what this does to your security before you use it. The people who listed this for fixing problems are basicly not using the correct syntax for mapping and lowering there security to allow anonymouse access to there boxes as it will allow anyone (user anonymous) to see all local user accounts and shared drives on your machine with tools like userdumb.

http://windowsitpro.com/Windows/Article/ArticleID/44413/44413.html

http://www.hsc.fr/ressources/articles/win_net_srv/ch04s06s10.html

http://online.securityfocus.com/infocus/1352

If you do want to allow anonymous access to shares use this from microsoft...

http://support.microsoft.com/kb/289655/

There are also a couple of other really great resources stickied on our sister site at Dev Hardware. They include Home Networking with Windows XP by moistmule and How to Diagnose a Slow or Broken Connection by Nilpo.

I have a 3-system Win XP Pro LAN through a router. Internet browsing works fine.
Computers 1 and 2 share files with no problem.
But system 3 is almost inaccessible to the other systems.
On #3, I can ping both the loopback address 127.0.0.1 and the local host IP address and default gateway. But I cannot ping the IP address of the #2 or #1, nor can I ping #3 from the other two systems.
From #2 or #1, I cannot see a shared folder on system #3. But from #3, I can browse a shared folder on the other two systems, though I cannot copy a file from there to #3. When I try to copy the file, I get the "access denied" error.




Windows IP Configuration



Host Name . . . . . . . . . . . . : archangel

Primary Dns Suffix . . . . . . . :

Node Type . . . . . . . . . . . . : Unknown

IP Routing Enabled. . . . . . . . : No

WINS Proxy Enabled. . . . . . . . : No



Ethernet adapter Local Area Connection 2:



Connection-specific DNS Suffix . :

Description . . . . . . . . . . . : NVIDIA nForce Networking Controller

Physical Address. . . . . . . . . : 00-11-D8-C9-2D-VX

Dhcp Enabled. . . . . . . . . . . : No

IP Address. . . . . . . . . . . . : 192.168.0.112

Subnet Mask . . . . . . . . . . . : 255.255.255.0

Default Gateway . . . . . . . . . : 192.168.0.1

DNS Servers . . . . . . . . . . . : 192.168.0.1

4.2.2.2