Possible Data Corruption w/ SNA Windows 95 Client Using TCP/IP

• Microsoft SNA Server version 2.11 and 2.11 Service Pack 1

SYMPTOMS

When you transfer a large amount of data using the Microsoft SNA Server Windows 95 client configured to use TCP/IP sockets to communicate with the server, some data bytes (15-20 bytes) may be corrupt when passed to the Win32 application. No APPC or CPIC errors will occur, though some data bytes received by the application may be corrupt.

This problem has been observed in the following configuration:

• SNA Server Windows 95 client software (from 2.11.sp1) configured to use TCP/IP sockets.
• Using a 32-bit Windows application that reads or receives large messages and simultaneously sends data.

• IBM Client Access/95, after retrieving a PTF download from the AS/400, which is unable to run due to random DLL errors when starting.
• Win32 APPC/CPIC database applications that receive large data messages. Part of the received data may be corrupt (or include "garbage" characters).

CAUSE

The SNA Server Windows 95 TCP/IP client transport was not properly receiving large TCP/IP data messages for a Win32 application, when the same application was simultaneously trying to send data. In one case, data corruption occurred.

STATUS

Microsoft has confirmed this to be a problem in the Microsoft SNA Server Windows 95 client included in SNA Server 2.11 Service Pack 1. This problem was corrected in the latest Microsoft SNA Server 2.11 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

   S E R V P A C K