FIX: The Dlc.sys driver does not receive frames that are larger than 100 bytes when you use an Ethernet adaptor that uses the Realtek 8139 chipset in Host Integration Server 2000

Systems Network Architecture (SNA) applications that communicate with an IBM mainframe or with an AS/400 system through 802.2 Data Link Control (DLC) connections do not receive data. This problem occurs if the frame that contains the data is larger than 100 bytes.

The actual symptoms that are experienced by users may vary depending on the SNA application that is used. If the application is a 3270 emulator, the 3270 emulator may not display a "USS MSG10" message when connecting to a mainframe application.

Note This problem only occurs when you use Ethernet adaptors that are based on the Realtek 8139 chipset.

The problem occurs because the data link control (Dlc.sys) driver does not read all the data that is received when a network adaptor driver uses the NdisIndicateReceive function to indicate received data. The NdisIndicateReceive function only passes part of the received data to the Dlc.sys driver. If the total amount of data that is received is larger than the part of the data that is passed in the initial call, the Dlc.sys driver is supposed to call the NdisTransferData function to receive the remaining data. The Dlc.sys driver assumes that the part of the data that is received in the initial NdisIndicateReceive function call is all the data that is received by the adaptor. Therefore, the Dlc.sys driver does not call the NdisTransferData function to read the rest of the data.

A supported hotfix is now available from Microsoft, but it is only intended to correct the problem that this article describes. Apply it only to systems that are experiencing this specific problem.

To resolve this problem, contact Microsoft Product Support Services to obtain the hotfix. For a complete list of Microsoft Product Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

Prerequisites

No prerequisites are required.

Restart requirement

You do not have to restart your computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace any other hotfixes.

File information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.

   Date         Time   Version            Size    File name
   --------------------------------------------------------------
   11-Nov-2004  01:01                    507,904  Hidlc.msi
   11-Nov-2004  00:19                        131  Snetcfg.cmd
   11-Nov-2004  00:38  5.2.3628.0         12,288  Snetcfg.exe      
   11-Nov-2004  00:19                      3,676  Netdlc.inf
   11-Nov-2004  00:38  6.0.1914.0         57,856  Dlc.sys
   11-Nov-2004  00:38  6.0.1914.0         10,240  Dlcapi.dll  

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

The Dlc.sys is updated to correctly call the NdisTransferData function when the NdisIndicateReceive API is used to indicate received data.

The problem that is described in the "Symptoms" section only occurs when Dlc.sys is bound to a network adaptor that has a driver that uses the NdisIndicateReceive API to indicate received data. The NdisIndicateReceive API is an obsolete NDIS function. For additional information about the obsolete NDIS function, visit the following Microsoft Developer Network (MSDN) Web site: