How to Troubleshoot Internet Connection Sharing Problems

ID: Q238135

The information in this article applies to:
  • Microsoft Windows 98 Second Edition
IMPORTANT: This article contains information about editing the registry. Before you edit the registry, make sure you understand how to restore it if a problem occurs. For information about how to do this, view the "Restoring the Registry" Help topic in Regedit.exe or the "Restoring a Registry Key" Help topic in Regedt32.exe.

SUMMARY

This article describes how to troubleshoot problems with Internet Connection Sharing (ICS) in Windows 98 Second Edition.


MORE INFORMATION

WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

For information about how to edit the registry, view the "Changing Keys and Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it. If you are running Windows NT, you should also update your Emergency Repair Disk (ERD).
Internet Connection Sharing (ICS) allows two or more computers to share one connection to the Internet. Before you install or use ICS, you should consult your Internet Service Provider (ISP) or read your ISP's Terms and Conditions of use Policy to determine if connection by more than one computer is allowed with your current account.

For more information about ICS, click the article number below to view the article in the Microsoft Knowledge Base:

Q234815 Description of Internet Connection Sharing
To install Internet Connection Sharing, follow these steps:
  1. Click Start, point to Settings, click Control Panel, and then double-click Add/Remove Programs.


  2. On the Windows Setup tab, click Internet Tools, and then click Details.


  3. Click to select the Internet Connection Sharing check box, click OK, and then click OK again.


  4. Follow the instructions on the screen to run the Internet Connection Sharing wizard




NOTE: ICS should only be installed on the computer that you use to connect to the Internet. This computer is called the Host. The other computers on the Local Area Network (LAN) that use the Host to connect to the Internet are called Clients.

For additional information about ICS requirements, click the article number below to view the article in the Microsoft Knowledge Base:
Q230140 Only One Internet Connection Sharing Host Is Required on a LAN
NOTE: The term Dial-Up Adapter is used in this article to refer to your modem but may also refer to an Integrated Services Digital Network (ISDN) or Asymmetric Digital Subscriber Line (ADSL) device.

Host Configuration

The first step in troubleshooting ICS is to make sure the correct components are installed on the Host after you install ICS. Check for the following two components in Network Properties
  • TCP/IP(Shared)-><Adapter>
  • TCP/IP(Home)-><Adapter>
where <Adapter> is your Dial-Up or network adapter.

To do this, follow these steps:
  1. Click Start, point to Settings, click Control Panel, and then double-click Network.


  2. On the Configuration tab, look in The following network components are installed box for the previously listed components


If either of the components appear in Network Properties but do not have the (Home) and (Shared) reference, ICS is not installed correctly and will not function properly. You may need to remove and install ICS again to resolve this issue.

For additional information about the ICS entries in Network Properties, click the article number below to view the article in the Microsoft Knowledge Base:
Q236465 Description of How ICS Appears in Network Properties
The TCP/IP(Shared) component should be the adapter you use to connect to the Internet and the TCP/IP(Home) component should be the adapter you use to connect to your LAN. If the TCP/IP(Shared) component is not present, the Host and Client will be unable to connect to the Internet. If the TCP/IP(Home) component is not present, the Host and Client machines may be unable to connect to each other on the LAN.

NOTE: If you know the adapter you use to connect to the Internet and the adapter you use to connect to the LAN, you can skip the following section titled Determining the TCP/IP(Shared) and the TCP/IP(Home) adapter..

Determining the TCP/IP(Shared) and the TCP/IP(Home) adapter.

  • Standard Dial-Up Networking Connections


    • For a standard Dial-Up Networking (DUN) connection, the Microsoft Dial-Up Adapter should be listed in Network Properties. To determine if DUN is used to connect to the Internet, check for an icon for your ISP in the Dial-Up Networking folder under My Computer.

    For a standard DUN connection, the following components should be listed in Network Properties for the Host:

    • TCP/IP(Shared)->Dial-Up Adapter
    • TCP/IP(Home)->Network Adapter

  • 3rd-Party Internet Dialer Connections


    • To determine if 3rd-party Dialer is used to connect to the Internet, check Network Properties for a listing for the 3rd-party Dialer's Dial-Up adapter. For ICS to function properly with a 3rd-party dialer, the Dialer software must use a 32-bit Dial-Up adapter. Some ISPs use their own Dialer to connect to the Internet. (For example, America Online (AOL).)

    For a 3rd-party Dialer connection, the following components should be listed in Network Properties for the Host:

    • TCP/IP(Shared)->3rd-Party Dialer Adapter
    • TCP/IP(Home)->Network Adapter

    For additional information about using third party dialers with ICS, click the article numbers below to view the articles in the Microsoft Knowledge Base:
    Q230233 How to Use AOL with Internet Connection Sharing
    Q229978 ICS Cannot Autodial 3rd-Party Internet Dial-Up Connections
    Note: For devices that use a network adapter, some ISP's record the "adapter address", sometimes called the "MAC Address", of the Network Adapter. Your ISP may only allow you to connect to the internet with that specific network adapter. If you want to use a different Network Adapter, you may need to contact your ISP for additional assistance.

  • Unidirectional Devices


    • For unidirectional devices, such as one-way cable modems, a connection to a source to send data and a connection to a source to receive data is required. ICS will not work with this type of configuration.

    For additional information about one way adapters, click the article number below to view the article in the Microsoft Knowledge Base:
    Q231648 ICS Does Not Function with Unidirectional Adapters
  • Two-way Cable Modems


    • For a two-way cable modem, the cable modem requires a network adapter in the Host computer. This configuration requires two network adapters to be installed in the machine, one for the cable modem and one for the LAN.

    For a cable modem connection, the following components should be listed in Network Properties for the Host

    • TCP/IP (Shared)->Network Adapter1
    • TCP/IP (Home)->Network Adapter2


    where the TCP/IP(Shared) is the network adapter connected to the cable modem, and TCP/IP(Home) is the network adapter connected to the LAN.

  • ADSL Devices


    • For a external ADSL device, the ADSL device requires a network adapter in the Host computer. This configuration requires two network adapters to be installed in the machine, one for the cable modem and one for the LAN.

    For a external ADSL device connection, the following components should be listed in Network Properties for the Host

    • TCP/IP(Shared)->Network Adapter1
    • TCP/IP(Home)->Network Adapter2


    where the TCP/IP(Shared) is the network adapter connected to the ADSL device, and TCP/IP(Home) is the network adapter connected to the LAN. NOTE: For an internal ADSL device, the ADSL device uses the standard Dial-Up Adapter to connect to the Internet. Internal ADSL devices should function the same as a standard dial-up networking connections.

  • ISDN Devices


    • For an ISDN device, both internal and external ISDN devices use the Dial-Up Adapter to connect to the Internet. ISDN devices should function the same as a standard dial-up networking connections.

Using the Icssetup.log File

To determine which adapters the Internet Connection Sharing wizard identified as potential Shared and Home Adapters, check the Icssetup.log file in the Windows folder. The Internet Connection Sharing wizard checks for possible adapters from the lists of adapters in Network Properties. If problems exist, verify that each of these adapters are also listed under Network Adapters in Device manager.

NOTE: The Intenet Connection Sharing wizard will never identify a Dial-Up Adapter as the Home Adapter.

Sample Icssetup.log file
Internet Connection Sharing Setup Log: Wednesday Mar 17 1999
Build Adapter ListBuild Adapter List - found: Dial-Up Adapter
Build Adapter List - found: Linksys LNEPCI II PCI Ethernet Adapter
Build Adapter List - found: Internet Connection Sharing
Find Internal Adapter Candidates, checking: Dial-Up Adapter NOT a
candidate, known special purpose adapter
Find Internal Adapter Candidates, checking: Linksys LNEPCI II PCI Ethernet Adapter IS a candidate
Find Internal Adapter Candidates, checking: Internet Connection Sharing NOT a candidate, known special purpose adapter
Find External Adapter Candidates, checking: Dial-Up Adapter IS a candidate
Find External Adapter Candidates, checking: Linksys LNEPCI II PCI Ethernet Adapter NOT a candidate, only valid Internal adapter
Find External Adapter Candidates, checking: Internet Connection Sharing NOT a candidate, known special purpose adapter
Find Internal Adapter Candidates, checking: Dial-Up Adapter NOT a candidate, known special purpose adapter
Find Internal Adapter Candidates, checking: Linksys LNEPCI II PCI Ethernet Adapter IS a candidate
Find Internal Adapter Candidates, checking: Internet Connection Sharing NOT a candidate, known special purpose adapter
Loaded external adapter: Dial-Up Adapter
Loaded internal adapter: Linksys LNEPCI II PCI Ethernet Adapter

TCP/IP(Home) and TCP/IP(Shared) appear on the wrong adapters.

To resolve this issue, follow these steps:
  1. Click Start, point to Settings, click Control Panel, and then double-click Internet Options.


  2. On the Connections tab, click Sharing.


  3. Under Connect to the Internet using, select the adapter for your Internet connection from the list.


  4. Under Connect to my home network using, select the adapter for your LAN from the list.


  5. Click OK, click OK again, and then restart your computer when you are prompted.


If the Sharing button is not present, this can be caused by the wrong versions of the Inetcpl.cpl and Inetcplc.dll files. For additional information on this issue, click the article number below to view the article in the Microsoft Knowledge Base:
Q236152 No Sharing Button After Installing Internet Connection Sharing
NOTE: If you remove or reinstall any components that appear in Network Properties on the Host, you must also remove and reinstall ICS.

Only one of the TCP/IP component is listed in Network Properties.

This issue can occur if one or more registry key is damaged. To resolve this issue, follow these steps: WARNING: Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk.

For information about how to edit the registry, view the "Changing Keys and Values" Help topic in Registry Editor (Regedit.exe) or the "Add and Delete Information in the Registry" and "Edit Registry Data" Help topics in Regedt32.exe. Note that you should back up the registry before you edit it. If you are running Windows NT, you should also update your Emergency Repair Disk (ERD).
  1. In Network Properties, write down the description of each of the adapters listed.


  2. In Registry Editor, open each of the following keys
    HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\Net\<nnnn>
    where <nnnn> is an incremental 4-digit number starting at 0000.


  3. Delete each key where the DeviceDesc entry does not match the description of one of the adapters in Network Properties.

    If there are multiple keys for the same adapter listed in Network Properties, delete each of the keys and then remove and reinstall the adapter in Device Manager. To remove the adapter in Device Manager, click Start, point to Settings, click Control Panel, double-click System, click the Device Manager tab, double-click Network adapters, click the adapter, and then click Remove. NOTE: You may need the original driver disk or software to reinstall the adapter after you remove it from Device Manager.


TCP/IP(Shared) and TCP/IP(Home) components missing.

This issue can occur if the Iphlpapi.dll file is the incorrect version or damaged.

To resolve this issue, extract a new version of the file from the Windows 98 Second Edition CD-ROM and then remove and reinstall ICS. To extract the Iphlpapi.dll file, follow these steps:
  1. Click Start, click Run, type sfc.exe in the Open box, and then click OK.


  2. Click Extract one file from Installation disk.


  3. Type iphlpapi.dll in the Specify the system file you would like to restore box, and then click Start.


  4. In the Restore From box, type the drive letter and path to the Windows 98 Second Edition Soure CD-ROM folder.


  5. In the Save File In box, type the full path to the \Windows\System folder (eg. C:\Windows\System), and the click OK.


  6. Click OK to use the default backup folder when you are prompted.


  7. Click OK and the quit System File Checker.


  8. Remove and reinstall ICS


Enable DHCP Services on Host

Without a proper IP address, the Client will be unable to communicate with the Host computer. If the Client computer does not obtain an IP address from the Host, the DHCP sevice may be disabled. To enable the DHCP services on the Host computer, follow these steps:
  1. On the Windows 98 Second Edition CD-ROM, open the Tools\MTSutil\ICS folder.


  2. Right-click the Dhcp_on.inf file, and then click Install.


  3. Restart Windows.


Client Configuration

Configure Client for DHCP

To configure the Client computer to obtain an IP address from the Host computer, follow these steps:
  1. Click Start, point to Settings, click Control Panel, and then double click Network.


  2. Click the TCP/IP component installed for the Network Adapter on you LAN.


  3. Click Properties.


  4. On the IP Address tab, click Obtain IP address automatically.


  5. On the WINS Configuration tab, click Use DHCP for WINS Resolution.


  6. On the Gateway tab, remove any gateways that may be installed.


  7. On the DNS Configuration tab, click Disable DNS.


  8. Click OK, click OK again, and then click Yes if you are prompted to restart the computer.


If you prefer to assign the Client IP information manually, or feel that the DHCP is not functioning properly, refer to the section entitled How to Assign a Static IP Address later in this article.

How to Assign a Static IP Address

Before you can assign a static IP address, you will need the DNS configuration information from your ISP. Or, on the Host computer, click Start, click Run, type winipcfg, and then click OK. Click ICShare Adapter, click More Info, note the DNS server address, and then click OK. After you obtain the DNS setting, follow these steps:
  1. Click Start, point to Settings, click Control Panel, and then double-click Network.


  2. Click the TCP/IP component installed for the Network Adapter on you LAN.


  3. Click Properties.


  4. On the IP Address tab, click Specify an IP Address.


  5. In the IP Address box, type 192.168.0.x (where x is a number between 2 and 254).

    NOTE: The IP address should be one that is not currently in use by another computer on your LAN.


  6. In the Subnet Mask box, type 255.255.255.0.


  7. On the WINS Configuration tab, click Disable WINS Resolution.


  8. On the Gateway tab, type 192.168.0.1 in the New gateway box, and then click Add.


  9. On the DNS Configuration tab, click Enable DNS, type the Client computer name in the Host box.

    NOTE: The Domain box can be left blank, and note that the computer name is case-senstive.


  10. In the DNS Server Search Order box, type the IP address for your ISP's DNS server, and then click Add.


  11. Click OK, click OK again, and then click Yes if you are prompted to restart the computer.


For additional information about how to assign a static IP address, click the article number below to view the article in the Microsoft Knowledge Base:
Q230150 How to Configure a Permanent IP Address for Network Devices

The Host Connects to the Internet but the Client Does not.

With the Host connected to the Internet, test the LAN and Internet connections by performing the following procedures:
  • Use Winipcfg Tool


    • To use the Winipcfg tool to verify the IP address, follow these steps:

    1. Click Start, click Run, type winipcfg, and then click OK.


    2. In the Ethernet Adapter Information box, select the network adapter


    3. Click Release, click Renew, and then click OK.


    If the IP address for the network adapter is 192.168.0.x (where x is a number between 2 and 254), the Client successfully obtained an IP address form the Host.

    If the Client does not obtain an IP address from the Host, you may need to enable the DHCP service on the Host or manually assign a static IP address to the Client.

  • Ping IP Address of Host


    • To use the Ping command to verify the functionality of Transport Control Protocol/Internet Protocol (TCP/IP), follow these steps:

    1. Click Start, point to Programs, and then click MS-DOS Prompt.


    2. At the command prompt, type ping 192.168.0.1, and then press ENTER.


    3. At the command prompt, type exit, and then press ENTER to return to Windows.


    If you receive a reply, the Client computer is able to communicate with the Host computer over the LAN with TCP/IP.

    If you do not receive a reply, troubleshoot the issue as a general network connection problem in Windows. For information about troubleshooting network connection problems in Windows, click the article number below to view the article in the Microsoft Knowledge Base:
    Q192534 Troubleshooting Windows 95/98 Network Connection Problems


  • Ping IP address on Internet


    • To ping the IP address of a Web site on the Internet, you first need to obtain the IP address of a Web site on the Internet from the Host. To obtain the IP address for a Web site, follow these steps:

    1. On the Host computer, click Start, point to Programs, and then click MS-DOS Prompt.


    2. At the command prompt, type ping <Web site name> (where <Web site name> is the Uniform Resource Locator (URL) of a Web site), and then press ENTER.

      NOTE: Some Web sites (such as www.microsoft.com) may not return a reply, if this occurs, try a different Web site.


    3. If the Web site returns a reply, you should receive the following message:
      pinging <Web site name> [xxx.xxx.xxx.xxx]...
      where <Web site name> is the Uniform Resource Locator (URL) of the Web site and xxx.xxx.xxx.xxx is the IP address of the Web site.


    4. Write down this IP address to use later.


    After you have obtained the IP address for a Internet Web site, to test the TCP/IP connection on the Client, following these steps:

    1. On the Client computer, click Start, point to Programs, and then click MS-DOS Prompt.


    2. At the command prompt, type ping xxx.xxx.xxx.xxx (where xxx.xxx.xxx.xxx is the IP address for the Internet Web site), and then press ENTER.


    3. At the command prompt, type exit, and then press ENTER to return to Windows.


    If you receive a reply, the Client computer is able to communicate with the Internet over the LAN with TCP/IP. If you do not receive a reply, refer the the Host Configuration section mentioned previously in this article for steps to configure and troubleshoot problems with the Host computer.

  • Ping Internet Name


    • If the Client can successfully ping the IP address of a website, use the Internet name to test the DNS configuration with ping. To do this, folow these steps:

    1. Click Start, point to Programs, and then click MS-DOS Prompt.


    2. At the command prompt, type ping <Web site name> (where <Web site name> is the Uniform Resource Locator (URL) of a Web site), and then press ENTER.

      NOTE: Some Web sites (such as www.microsoft.com) may not return a reply, if this occurs, try a different Web site.


    If you receive a reply, the Host and Client computer are configured and working correctly. NOTE: If your browser is still unable to open a Web Site by name, check the browser's connection settings and make sure it is configured to use the LAN to connect and that no proxy servers are configured.

  • Open IP Address in Browser


    • To test the browser by attempting to open a Web site by the IP address, follow these steps

    1. Click Start, click Run, type http://xxx.xxx.xxx.xxx (where xxx.xxx.xxx.xxx is the IP address of the Web site), and then click OK.


    If the Web site is displayed, the browser is functioning properly and there may be a problem with Domain Name Server (DNS) resolution.

    For additional information about configuring DNS, click the article number below to view the article in the Microsoft Knowledge Base:
    Q229974 Connection Error Messages When You Use ICS with an FQDN
    If the Web site is not displayed, there may be a problem with Winsock on the computer.

    For information about possible Winsock issues, click the article number below to view the article in the Microsoft Knowledge Base:
    Q188952 "Internal Error Occurred" Error Message Using Internet Explorer

Additional query words:

Keywords : kbenv kbnetwork kbtshoot win98se
Version : WINDOWS:
Platform : WINDOWS
Issue type : kbhowto


Last Reviewed: December 3, 1999
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