SNA Server Application Exception When Using SET_TP_PROPERTIES

ID: Q193908

The information in this article applies to:

Microsoft SNA Server, versions 3.0, 3.0 SP1, 3.0 SP2, 3.0 SP3, 4.0, 4.0 SP1

SYMPTOMS

An Advanced Program-to-Program Communication (APPC) application that uses SNA Server's Sync Point feature can use the SET_TP_PROPERTIES verb to set its Logical Unit of Work Identifier (LUWIDs) by specifying an existing value or by requesting the SNA Server to generate new ones. The SNA Server SDK documentation for the SET_TP_PROPERTIES verb indicates the following for its opext parameter:

opext
Supplied parameter. Specifies the verb operation extension. The AP_EXTD_VCB bit must be set to indicate that the set_tp_properties structure requires Sync Point support.

If the AP_EXTD_VCB bit is in the opext parameter of the SET_TP_PROPERTIES verb, a primary return code of 0xFFFF will be returned when the application runs this portion of code. This error indicates an invalid opcode.

If the AP_EXTD_VCB is not set in the opext parameter, the SNA Server service will generate an application exception when the application is started.

The application exception will generate a Drwtsn32.log if Drwtsn32.exe is configured as the default debugger on the SNA Server system. In addition, an Event 624 may be logged in the Windows NT Application Event Log indicating that a Snadump.log file was generated.

CAUSE

The application exception in the SNA Server service only occurs when the SET_TP_PROPERTIES verb requests that a new LUWID be generated by the SNA Server. When generating the new LUWID, the SNA Server tries to use a resource control block that does not exist, which results in the application exception. In addition, the SNA Server SDK incorrectly indicates that the AP_EXTD_VCB bit must be set for the opext parameter of the SET_TP_PROPERTIES verb.

RESOLUTION

Microsoft has confirmed this to be a problem in SNA Server versions 3.0, 3.0 SP1, 3.0 SP2, 3.0 SP3, 4.0, and 4.0 SP1. We are researching this problem in SNA Server version 3.0 and will post more information here in the Knowledge Base as it becomes available.

This problem was corrected in the latest SNA Server version 4.0 U.S. Service Pack. For information on obtaining this Service Pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K

Additional query words:

Keywords :
Version : WINDOWS:3.0,3.0 SP1,3.0 SP2,3.0 SP3,4.0,4.0 SP1
Platform : WINDOWS
Issue type : kbbug