Sybergen Access Server and SyGate Frequently Asked Questions

|| General || Configuration || Troubleshooting ||

General Questions

1. What security does offer and how does it protect me from hackers?

• Built-in enhanced security mode blocks incoming TCP/IP connections to the Server except for TCP/IP Ports 1000 to 5000. This allows the Server to still function on the Internet for all other Ports 0 to 65535.
• ONLY allows connections into your local area network if they are FIRST established from the local area network.
• Black and White lists where you can restrict access TO and FROM your local area network based on TCP/IP Ports, IP Address, and Schedule.
• Application Rules where TCP/IP connection parameters can be defined based on what Ports are being used and how to react based on the TRIGGERING transaction.
• Sybergen Secure Desktop (sold separately) is very popular with both Sybergen Access Server and SyGate users as it can close ALL INCOMING and OUTGOING ports on the SERVER, and also offers scheduling, security levels, and more configurable security parameters.

2. What types of cable modems do Sybergen's products work with?

Two-way cable modems work fine with Sybergen Access Server and SyGate. Most one-way cable modems will not work with Sybergen Access Server or SyGate such as the Motorola Surfboard 1000. However some one-way cable modems such as the Motorola Surfboard 1200 that have a built-in analog modem and cable modem work fine.

3. Is client software or any special configuration required?

No special settings or additional software is required. There is optional client software for administration of Internet sharing from a client computer. The client software also has diagnostics to configure the clients network settings automatically. Remote administration of Internet sharing is also possible without the client software through Telnet by specifying the SyGate server's TCP/IP address and port 7323 (telnet 192.168.0.1 7323).

4. Can others dial-in to share my Internet connection?

Our software is designed to send and receive from the local network to the Internet so the dial-in connection must be to a client computer and not to the server computer.

5. Are two network adapters required?

Our software is designed to send data from one adapter to another adapter, requiring two network devices (a dial-up modem and a network card OR two network cards). A separate network adapter is required if you are using a Ethernet based cable or DSL modem. If a standard Dial-up modem or DirecPC is being used for the Internet connection, only one network adapter is needed for your local network.

6. Why our software instead of Microsoft's Internet Connection Sharing (ICS)?

• Fully compatible with all current Windows operating systems - doesn't require an upgrade from a previous operating system.
• Supports 3, 6, 10, 25, and unlimited client computers instead of just five client computers.
• Built-in diagnostics to detect potential problems with your Internet connection as well as your local network settings.
• Built-in support for Virtual Private Networking (VPN), NetMeeting, ICQ, and several complex network games and business applications.
• Strong configuration capabilities through application rules - allows nearly any Internet application to work from your entire network.
• Enhanced security mode to protect from Internet hackers by blocking incoming data that is not requested. Our software blocks incoming connection attempts to the server on all ports except for 1000-5000.
• Black and White list control to define and schedule where your networked computers can go on the Internet and what they can and can't do.
• Detailed traffic logs that shows who was using the Internet connection at any given time and what they were doing.

7. What if I have more computers than my license is for?

Our licensing is for the server computer and the total number of connections going through it (a three-user license supports two networked computers and the server computer). If you have more computers than your license is for and one of your users closes their Internet applications, another user could then have access. If your Internet requirements grow, Sybergen offers license upgrades to allow more simultaneous connections to go through.

8. Is Microsoft NetMeeting supported?

NetMeeting works through our software without any customization. The only limitation is that the client computers will not be able to receive calls through the server computer without first being logged into a directory service first. Directory services such as Internet locator servers (ILS), MSN Messenger, or ICQ are common ways to setting up your systems for incoming calls with NetMeeting.

9. Does SyGate support Windows 2000?

SyGate version 3.1 (or higher) works fine with Windows 2000. To configure Windows 2000 as a SyGate client for Internet through a SyGate server, set the preferred and alternate DNS entries in the TCP/IP properties to be the service providers recommended DNS settings and set the Gateway entry to be the SyGate servers local TCP/IP address (i.e. 192.168.0.1). To use Windows 2000 as a SyGate server, you cannot have Windows 2000's Internet Connection Sharing (ICS) enabled.

10. Does SyGate support Sybergen Secure Desktop (formerly SyShield)?

SyGate 3.1 and higher works well with Sybergen Secure Desktop, however the version of Sybergen Secure Desktop you are using with SyGate must be specific. Version 3.1 of SyGate works with SyShield 1.1. Version 3.11 of SyGate works with Sybergen Secure Desktop 1.11. Mismatching versions of these products can result in system instability so we recommend checking the system requirements for either software before installing. Sybergen Secure Desktop can greatly benefit a SyGate servers security by blocking more types of transactions and  because it offers more features such as ultra-high security (which will block all incoming and outgoing communication on the SyGate computer but not the SyGate clients). Sybergen Secure Desktop can also be installed on the SyGate client computers to protect their Internet connection abilities as well as to provide local network security. SyGate combined with Sybergen Secure Desktop provide a very powerful firewall and Internet access solution.

11. Does SyGate support America Online?

SyGate fully supports AOL dial-up services and AOL 4.0 and AOL 5.0 special software. SyGate allows the sharing of a AOL account to access the Internet from a local network. SyGate implements a special built-in function to allow users on a local network to automatically trigger a single SyGate server computer with AOL software a dial-up and login to AOL and then share it's Internet connection. With SyGate's Black and White list feature, users can also further secure and enforce AOL's content filtering functionality. AOL 5.0 software requires SyGate 3.11 or higher.

12. Does SyGate support multiple subnets?

You can access a SyGate server from multiple subnets if they are on the same physical network. If planning to use a SyGate server computer on separate subnets in your network, keep in mind that SyGate cannot route to multiple adapters (only from one Ethernet card to another). SyGate can also be used as a firewall from one subnet to another to protect a particular group of systems on your network (i.e. accounting). If used as an internal firewall, note that you will not be able to route NetBIOS traffic through it (for Windows domain login, file and printer sharing, etc.).

13. Does SyGate support DirecPC?

Yes. However we have had reports of performance issues on some configurations due to packet size problems between the SyGate clients and what DirecPC expects to send out. We have found that changing MTU on the SyGate client computers to 1466 can greatly improve performance when using DirecPC as the Internet connection method. MTU can be changed manually for the Ethernet card being used in the System registry if you are familiar with this procedure, or by using a simple public domain utility such as TweakDUN. 

Configuration

14. I already have a working TCP/IP network, how do I configure it to use SyGate?

Install SyGate on the computer with the Internet connection, this will be the SyGate server computer. Then enter the private TCP/IP address (i.e. 192.168.0.1) that is being used on the SyGate server computer into both the "Gateway" and "DNS" settings within the TCP/IP properties on all other computers. They will then go to the SyGate server computer as their gateway and DNS server when an Internet connection is needed.

15. What type of virtual private networking (VPN) works with SyGate?

SyGate works with Microsoft VPN (PPTP), ShivaVPN, BayVPN, AltaVista Tunnel, and various IPSec clients. SyGate currently supports one VPN connection from the SyGate network to a VPN host on the Internet. If more than one VPN connection is needed, we recommend disconnecting one prior to connecting the other - failure to do this may result in the first connection getting dropped automatically. You currently cannot host a VPN server behind the SyGate server computer. Currently hosting a VPN server on the SyGate server may result in unpredictable behavior due to multiple services attempting to route the same data. We have an example Apprule for BayVPN clients in our Apprule.cfg file (in the SyGate directory on your hard drive) that you can enable. Microsoft PPTP does not need any Apprule settings (support for it is built into SyGate).

16. How can I control Internet connectivity for my network through SyGate?

You can configure SyGate to only allow or to deny certain connections from your network through SyGate's black and white list feature. You can manage the connections you want to allow by port number and IP address. You can also specify time periods for each restriction you define. You can set restrictions for individual computers (by their IP address) or for the entire network (by entering 0.0.0.0 as the IP address). The 0.0.0.0 parameter can be used to specify ALL internal addresses as well as ALL external addresses. If you need further instructions for SyGate's black and white list functions, go to the help system included with the SyGate software by clicking on the "?" icon in the SyGate manager program.

17. What does SyGate's APPRULE.CFG file do?

The "Apprule.cfg" file in the SyGate directory is used to allow unique applications on your network to function on the Internet through SyGate. This file's default settings allow most popular applications to work by default. The default "Apprule.cfg" also has several predefined examples for various applications to run on your network including Quicktime, FTP, Telnet, HTTP servers, Email servers, and online games. You can enable these settings by editing this file with a text editor, removing any comment flags (#), specifying the TCP/IP and port settings you want to enable, saving the file, and then stopping and starting the SyGate service using the SyGate manager application. We have more details on the Apprule.cfg file at http://www.sybergen.com/support/conf_sg.htm. Also note that the "Apprule.cfg" file settings on the SyGate server only apply to the computers running behind SyGate - not to the SyGate server itself. Apprule's do not need to be defined for applications running on the SyGate server computer.

18. How do I configure SyGate to use backup DNS in case the primary DNS fails?

If the first DNS server listed in the TCP/IP properties on the SyGate server computer fails, your networked computers may all of a sudden not be able to communicate on the Internet. This can be corrected by using SyGate's built-in DHCP server and specifying your service providers recommended primary and backup DNS servers in the advanced settings (available in the SyGate manager programs configuration screen). This issues can also be corrected by manually specifying primary and backup DNS entries in the DNS tab of the TCP/IP properties on each computer.

19. How do I configure SyGate so my network is shown in the SyGate manager?

The SyGate manager program looks for and communicates with other SyGate manager programs on your network. If you install SyGate client software and start the SyGate manager program, SyGate manager will display all other systems also running the SyGate manager program in the SyGate Network Neighborhood. If the SyGate manager program is not running on any of the network computers, they will not be displayed in the SyGate manager program.

20. I can't get more than one player on the MSN Gaming Zone or MPlayer?

These online services currently limit connections to their network to one player per public IP address, limiting your ability to connect more players from your local network. We have found other online networks that support many of the same games such as http://www.heat.net work fine.

21. How do I configure Ident for SyGate?

Ident is used to by various IRC applications (IRC, mIRC, and others) to identify you to host computers on the Internet. To get Ident to operate properly through SyGate, install IRC or mIRC (or another IRC tool) on the SyGate server computer. Then select any options to enable Ident on this computer in the programs connection settings (usually "File, "Setup, "Ident"). Keep the IRC application running on the SyGate server computer (you don't need to connect to any site from this particular IRC installation for Ident to work).

22. How do I configure Net2Phone for SyGate?

Net2Phone is an Internet application used to communicate directly with other Net2Phone users on the Internet. For Net2Phone to function with SyGate, you need to add the following lines to the "[Config]" section of the "NET2FONE.INI" file (located in C:\WINDOWS\NET2FONE.INI)...

TCPPORT=6613
UDPPORT=6613

If you have multiple Net2Phone users on your SyGate network, you need to duplicate these lines in the same file and change 6613 in the above example to 6614, 6615 - add TCPPORT and UDPPORT settings for each user. If you need to run Net2Phone on multiple Sygate clients, you will also need to change the default Apprule.cfg file in the SyGate directory accordingly.

23. How do I configure LapLink for SyGate?

To allow LapLink to operate on your SyGate network, you must edit the "LLW.INI" file located at "/WINDOWS/TSI32/LLW/LLW.INI". After opening the "LLW.INI" file, scroll to the "[TCP/IP]" section and add the following line:

ClientPort=xxxxx

Where xxxxx is any number between 1025 and 65535 (do not use 1547). A number above 30000 might be best, to avoid conflicts. Default TCP/IP Port assignments can be found in RFC1700. Then, add the following lines to the Apprule.cfg file (located in the SyGate directory):

:INIT "Laplink Host"
IN TCP 1547 1547 192.168.0.10x 0 60000 -
:SUB
:END
:INIT "Laplink Guest"
IN TCP xxxxx xxxxx 192.168.0.10x 0 60000 -
:SUB
:END

Where xxxxx is THE SAME NUMBER you used in configuring "ClientPort" on the LapLink machine, and 10x it the correct number for the machine you are connecting to with LapLink. Save the Apprule.cfg file and then restart the SyGate service using the SyGate manager program for the settings to take effect.

24. How do I configure my Macintosh for an Internet connection through SyGate?

To configure your Macintosh to work on your network behind SyGate, you can configure the Macintosh TCP/IP control panel for "Configure using DHCP Server" if you're using SyGate's built-in DHCP server. If you select "Configure Manually", set the Router and Name server address entries to be the SyGate servers TCP/IP address (i.e. 192.168.0.1) and assign the Macintosh it's own TCP/IP address in the same range (i.e. 192.168.0.2).

25. How do I configure NTP (Network Time Protocol) for SyGate?

# NTP
:INIT "Network Time Protocol"
OUT UDP 123 123 0.0.0.0 0 -
:SUB
IN UDP 123 123 0.0.0.0 0 -
:END

Make sure that the tab and spacing are the same as the existing Apprules and then save the Apprule.cfg file, then restart the SyGate service using the SyGate manager program.

26. How do I configure the Auto hang-up feature of SyGate?

The auto hang-up feature of SyGate is used to disconnect SyGate's dial-up connection if no activity is detected within the specified period of time. This function cannot be disabled, however if you wish for SyGate not to disconnect you can enter up to six 9’s in this field (999999) which will keep SyGate online for several days if there is no Internet activity. If there is Internet activity during any period, the counter will start over from 0-999999 when the activity stops.

27. What is the option for username and password in SyGate used for?

This information is needed by SyGate for when SyGate dials the Internet connection for the Dial-up networking profile selected. The username and password must match exactly what is already entered into the Dial-up networking profile. The Dial-up networking profile must also be configured to remember the password that is entered (Save password). You can check this by using the Dial-up networking profile on the SyGate server computer to make sure it works.

28. How do I configure RealJukebox by RealNetworks for SyGate?

RealAudio software works fine with SyGate networks without any special configuration, however RealJukebox requires configuration of SyGate as SyGate cannot route CDDB data via DNS forwarding. To correct this problem, specify the service providers recommended DNS settings in the TCP/IP properties DNS tab on the networked computer -- or alternatively you can use SyGate's built-in DHCP server with Advanced settings and specify the service providers DNS servers in this dialog.

Troubleshooting

29. I cannot communicate with my service providers email, news, and web servers?

To find your domain suffix, do the following on the SyGate server while connected to the internet:

1. from a dos prompt, type NSLOOKUP

2. then type the IP address of your Default Gateway

3. That should show you your Domain Suffix plus some extra information

for example:

you might see proxy.frmt1.sfba.home.com

your domain suffix is everything after proxy. (see below)

from the above instructions I found proxy.frmt1.sfba.home.com

my domain suffix is frmt1.sfba.home.com

my email server is mail.frmt1.sfba.home.com

With the above information:

1. Remove any domain suffix (host name) entries on your SyGate client machines.

2. Instead of simply entering mail for your email server, enter the full address of your email server in your email program. (I suggest you simply add "mail" to the beginning of the domain suffix that your ISP gave you or that you found in the above steps.)

If that doesn't work then from the SyGate server, ping your mail server. (try typing 'ping mail' at a dos prompt) Once you find the IP address you should use it for your email server on the client machines.

30. SyGate dials out if I do anything on my network, how can I stop this?

If using Windows NT 4.0 on your network or as the SyGate server, edit the TCP/IP properties and check the "WINS" tab to verify that the option to "Enable DNS for Windows Resolution" is not enabled. Having this option enabled could cause local network activity to attempt to contact the DNS server specified in TCP/IP.

31. How should I troubleshoot lock-ups or system crashes with SyGate?

If your system locks-up or crashes when installing or running SyGate, we recommend performing the following troubleshooting steps...
-  Re-download SyGate to ensure the program fully transferred correctly to your system. SyGate may have been be damaged during usage or during your initial download so this is a good step to take prior to further action. After downloading, fully uninstall SyGate, restart, and then install this newly downloaded version.
-  Shut down any other services or applications not essential to the system running Windows and attempt to duplicate the problem. If another service or application is isolated to conflict with SyGate, please let us know immediately.
-  Update your operating system with the latest service packs or updates available. If using Windows NT 4.0, we recommend re-applying the last service pack applied to the system again. This step will frequently repair problems with Windows NT.
-  Check the modem or network card manufacturer for updated device drivers and install any updates that are available. This step will also frequently repair problems of this type.
-  Check to verify that your equipment is supported by SyGate. SyGate will work with all known ISA and PCI Ethernet network adapters, analog modems, and DirecPC cards. SyGate currently does not support multi-processor enabled Windows NT. SyGate also currently does not work with ATM or TokenRing adapters. If you have a specific device you wish for SyGate to work with, please let us know.

32. My local network stopped working after installing SyGate?

If using Windows 95 or Windows 98, verify that file and printer sharing is installed and enabled in the Network control panel. If it is or if using another operating system, verify that the "subnet mask" is the same on all computers on the network. Set the "subnet mask" entry in TCP/IP properties on all of the computers to be the same. If subnet mask is the same on each computer and the issue continues, go to the Network control panel and check the network bindings and then select okay. Restart the computer to see if the network has restored itself. If not, go back to the network control panel and remove and then add back the TCP/IP entry. These steps usually resolve problems of this type.

33. Networked computers are not able to browse the Internet through SyGate?

Make sure that your browser application or Internet options control panel is not configured to use a proxy server for your Internet connection. If no proxy is specified in your settings, first make sure the Internet browser is working on the SyGate server computer, then use the following settings on your systems...

SyGate Server computer
IP Address: 192.168.0.1
Subnet Mask: 255.255.255.0
Gateway: Blank
DNS: Leave this setting alone (if the SyGate server can browse, this is okay)

SyGate Client computer
IP Address: 192.168.0.2
Subnet Mask: 255.255.255.0
Gateway: 192.168.0.1
DNS: 192.168.0.1

34. My network card and hub show traffic when SyGate Manager is running?

The SyGate manager traffic you see is because the SyGate manager is communicating information for other SyGate manager programs on your network. Each SyGate manager program will send 1 packet to the network every 1-2 seconds. To stop this activity, you must close the SyGate manager program and then remove it from your task bar (right click on it and choose exit).

35. My network connections stopped working through SyGate.

If your networked computers were working through SyGate and then stopped, the issue is most likely one of two different problems. The first, SyGate may have temporarily lost contact with your ISP. If this occurs, going to the SyGate manager program and stopping and starting the SyGate service should fix the problem. If this does not resolve the issue, your ISP's primary DNS server may be down. Check the primary DNS setting in the SyGate servers TCP/IP properties. The primary DNS IP address will be the first item listed in the DNS tab. Once you know this IP address, go to a command prompt on the SyGate server computer and "ping" it as follows.. ping x.x.x.x where "x.x.x.x" is the IP address of your primary DNS server. If there is no response, then go back to the SyGate servers TCP/IP properties DNS tab and reverse the order listed of the primary and secondary DNS servers.

36. My workstation(s) sharing the PPPoE connection does not work properly with SyGate/Access Server, what should I do?

Certain DSL service providers such as Bell Sympatico, Bell Atlantic, Bell South, and Pacific Bell are currently offering a unique connection method for their service called PPP over Ethernet. PPPoE has not been specifically designed for our software, however, our users have reported that it works well if you reduce the MaxMTU setting until no fragmentation is detected from a ping test on the client system.

37. I'm having difficulty during installation on SyGate/Access Server with PPPoE connection, how do I install it? 

During installation, skip the diagnostic and exit this test.  Start SyGate/Access Server manager and skip the diagnostic phase again.  Open SyGate/Access Server manager one more time and it will prompt you with a configuration screen.  

For WinPoET users, select "through dialup networking" as your connection method and the proper adapter for your LAN (Ethernet adapter) and Internet connection (Ethernet adapter) under Network Adapter Settings.  After completion, you must shutdown and reboot the system before using this application.

For NTS users, select "through Cable modem/DSL" as your connection method and the proper adapter for your LAN (Ethernet adapter) and Internet connection (Network TeleSystems PPPoE) under Network Adapter Settings.  After completion, you must shutdown and reboot the system before using this application.

38. How do I know what Max MTU setting I need for my server and workstations(s)?

On the server, you do not need to make any changes since it is not affected.

On a client system, you will need to perform this test to obtain the best results.

Open a DOS/Command Prompt and type "ping -f -l 1462 http://www.my-isp-name.com/">www.my-isp-name.com"

- If you get "Packet needs to be fragmented but DF set" you must reduce the packet size (e.g. 1430 or 1400) repeat the test again. (Windows default is 1500)

- If you get 4 replies from your ISP, you will then use this packet size as the MTU setting for the workstation.

*Sympatico users should refer to your ISP recommendation

39. Do you have a utility to change the MaxMTU setting related to PPPoE software?

No, we do not currently provide a utility to change the MaxMTU settings. However, based on user's feedback, the following shareware will simplify the configuration of the MaxMTU settings on your workstation(s) but the result may vary.

http://www.mjs.u-net.com/home.htm - MTUSpeed Pro (for PC users)
http://www.pattersondesigns.com/tweakdun/ - TweakDUN (for PC users)

http://www.sustworks.com/products/product_otat.html - OT Advanced Tuner (For Mac users)

If the utility does not work for you, or if you prefer to set it manually, locate the proper registry entry and create/add the tested MTU value into the client system.

* Making incorrect changes to the System Registry may cause your system to not operate properly. We strongly recommend someone familiar with the Microsoft System Registry to make these changes. We also recommend backing up your system registry before making manual changes to it.

Windows 95/98

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Class\NetTrans\000x\MaxMTU="1462" (STRING Value)

- If you are unclear on which 000x folder is your current Ethernet Adapter, exit registry editor, go into your Ethernet TCP/IP setting under network configuration, enter an IP address manually, close and reboot the system. After reboot, get into the registry editor and locate HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Class\NetTrans\000x\IPAddress you will then find one of the 000x folder contains the data (e.g.192.168.0.2) you just entered. Once you have found the proper entry, click on "Edit", "New", "STRING", type "MaxMTU" and <enter>, right click on "MaxMTU", select "Modify", select "Decimal" and then enter "1462". Save the registry, close the registry editor and reboot this system.

Windows NT

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\"Ethernet-adapter name"\Parameters\Tcpip\MTU="1462" (DWORD Value)

- If you are unclear on which "Ethernet-adapter name" folder is your current Ethernet Adapter, exit registry editor, go into your Ethernet TCP/IP setting under network configuration, enter an IP address manually, close and reboot the system. After reboot, get into the registry editor and locate HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\"Ethernet-adapter name"\Parameters\Tcpip\IPAddress, you will then find one of this folder contains the data (e.g. 192.168.0.2) you have just entered in hexadecimal. Once you have found the proper registry entry, click on "Edit", "New", "DWORD Value", type "MTU" and <enter>, right click on "MTU", select "Modify", select "Decimal" and then enter "1462". Save the registry, close the registry editor and reboot this system.

Windows 2000

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}\MTU="1462" (DWORD Value)

- If you are unclear on which {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} folder is your current Ethernet Adapter, exit registry editor, go into your Ethernet TCP/IP setting under network configuration, enter an IP address manually, close and reboot the system. After reboot, get into the registry editor and locate HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces\{xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}\IPAddress, you will then find one of these {Key} folders contains the data (e.g. 192.168.0.2)" you have just entered. Once you have found the proper registry entry, click on "Edit", "New", "DWORD Value", type "MTU" and <enter>, right click on "MTU", select "Modify", select "Decimal" and then enter "1462". Save the registry, close the registry editor and reboot this system.

40. SyGate 3.1 with Windows 95 dial-up networking disconnects on first attempt but stays connected on the second attempt?

This issue exists with Windows 95 Dial-up networking 1.2. Upgrading Windows 95 to dial-up networking 1.3 or higher and Winsock2 will fix this problem. Following are the links for these upgrades...

http://www.microsoft.com/windows95/downloads/contents/WURecommended/S_WUNetworking/dun13win95/Default.asp - Dialup networking 1.3

http://www.microsoft.com/Windows95/downloads/contents/WUAdminTools/S_WUNetworkingTools/W95Sockets2/Default.asp - Winsock 2

Both DUN 1.3 and Winsock 2.0 must be installed prior to installing the update below.

http://www.microsoft.com/windows95/downloads/contents/WURecommended/S_WUNetworking/dunwinsky2k/Default.asp - Microsoft DUN 1.3 and Winsock 2 Year 2000 Update (Update Only)

This issue does not exist with Windows 98 or higher.