Win98 networked to Win2k

Do you have any software running on the Windows 98 machines that perform real-time or high-priority network traffic analysis or file scanning, such as an antivirus package or firewall software? If so, reboot the machine, temporarily disable that software, and transfer several large files back and forth to test.

You may want to try eliminating other programs starting up in the background within Windows 98 that could be causing problems (even if they do not seem directly related to networking or file scanning). See the following Dell Knowledge Base article for further information:

What is the Microsoft® System Configuration Utility (MSCONFIG)?

Look at routing table and protocol statistics for TCP, UDP and IP by using the netstat command. Try the following commands. Typing netstat /? will give some minimal help on the command or look at netstat command line parameters explained link

(d) netstat -a Displays all network connections and listening ports

(e) netstat -e Displays Ethernet statistics.

(f) netstat –r Displays the contents of the routing table.

(g) netstat –e –s | more Local machine stats are shown for TCP, UDP and IP

Win98 machines look essentially like MSDOS Network Clients.
There is a ton of information from Microsoft But it is not free nor are network design engineers.




Win2000 has a problem with Packet size during large file transfers and can essentially
timeout and clog the network due to excessive collisions based on the MTU and Packet size for MSDOS windows.

This behavior occurs because the MS-DOS sender drops packets during the transmission. Windows 2000 uses a different TCP receive window size of 17 KB for Ethernet (8 KB in Windows NT 4.0). MS-DOS sends back-to-back packets in an attempt to fill the receiver's buffer that is flooding its network adapter. The MS-DOS real mode network adapter driver is unable to keep up with the stream of packets sent by the MS-DOS TCP/IP stack, which results in packet losses. The network adapter driver drops packets before they are placed on the wire.

http://support.microsoft.com/default.aspx?scid=kb;EN-US;120642

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

To work around this problem, set the TCP receive window size in Windows 2000 to a value equal or less than 8 KB:
Start Registry Editor (Regedt32.exe).
Locate the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\tcpip\Parameters

On the Edit menu, click Add Value, and then add the following registry value:
Value Name: TcpWindowSize
Data Type: REG_DWORD
Value: 8192

Quit Registry Editor.


The Maximum Segment Size (MSS) is calculated from the Maximum Transmission Unit (MTU) reported by the NDIS driver (network card). For example, Ethernet = 1460; 4 MB Token Ring = 4128; 16 MB Token Ring = 17888.

When the MS-DOS client sends the first segment of data, the client may send an undersized packet using a TCP window value that is less than the MSS. A network trace shows this value in the TCP header. For Ethernet, the Windows value in the TCP header looks similar to the following example:
TCP: Window = 1450 (0x5AA)

If this situation occurs, configure the TCP receive window size on the Windows 2000-based computer to be a multiple of the TCP window the client uses. In this example, the value is a multiple of 1450 instead of 1460, so the TCP receive window size is 7250 (1450 x 5).

You should not reduce the TCP receive window size to fix network problems. Reducing the window size makes symptoms less apparent, but does not resolve the problem.

You can set the TCP receive window size using the TcpWindowSize registry key.

Message Edited by SpeedStep on 01-07-2004 02:40 PM

I have tried eliminating the virus programs, and all Norton utilities.  This has improved the performance but has not entirely eliminated the problem.

RichAlonso

 

I tried changing the registry as you suggested.  This did not help.  The win98 computers are still hanging (intermittently) when trying to access large files.

I input the value 8192 as a decimal value.  Is this correct?

I didn't understand the the second part of the message.  How do I get the TCP:window = value?

Finally, If I were to upgrade these machines to windows XP would these problems go away?

Any help would be greatly appreciated.

RichAlonso

The MTU  key is a STRING value and is located under MSTCP. Remember you may have to create the key yourself.

[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP] "DefaultRcvWindow"="32767"

REGEDIT4

[HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP]
"DefaultRcvWindow"="32767"

If you are using a Hub I would suggest getting a Switch instead and then making sure that all of your devices are running CAT5 cables at 100 Megabit full duplex.

A Linksys Firewall Router would do the trick. A bit more expensive but also can prevent nuking from the outside. There are many TCP/IP Patches for the WIN98 stack as well as problems associated with the WIN98 Client. There is even a Client upgrade for WIN98 on WIN2000 networks.

http://www.microsoft.com/windows2000/server/evaluation/news/bulletins/adextension.asp

http://www.microsoft.com/windows2000/server/evaluation/news/bulletins/l2tpclient.asp

Affected System:
=================
- Microsoft Windows 95
- Microsoft Windows 98
- Microsoft Windows 98 Second Edition

 

Power Management may also be an issue.

Windows 98 Second Edition may hang when the machine is being suspended.

This is due to an obscure bug, which exhibits itself when the path specified for the swapfile in the [386Enh]

section of the System.ini file includes a lowercase drive letter.

The name of the swapfile used by Windows 98 can be changed by adding a PagingFile= line to the [386Enh] section

of the System.ini file. If the path specified for the swapfile includes a lowercase drive letter, it can cause

Windows 98 Second Edition to occasionally hang during a suspend.

To fix this:

Select Start > Run and type msconfig in the Open: box, then press OK

Select the System.ini tab

Click the + sign next to the [386Enh] section to expand it

Select the line PagingFile= and click Edit

Change the lowercase drive letter to uppercase

Click Apply and OK

When prompted, restart your computer

When you try to resume your computer from Suspend mode, your computer may take 30 seconds or more to resume. This behavior can occur if you have a network adapter that is not attached to an active network connection. When your computer enters Suspend mode, the drivers for your protocols are unloaded. When you try to resume your computer, Windows attempts to load the drivers for your protocols, and then bind them to the network adapter. If an active network connection is not found, a time out occurs and causes the delay.