TN3270 Server Access Violation in SetBestGroups()

The information in this article applies to:

• Microsoft SNA Server, version 3.0 Service Pack 1 (SP1)

SYMPTOMS

When a TN3270E print emulator attempts to open a printer session through the SNA Server 3.0 Service Pack 1 TN3270 Server, the TN3270 server may encounter the following access violation:

   Application exception occurred:
      App: tn3servr.DBG (pid=<process id>)
      Exception number: c0000005 (access violation)

   [data omitted]

   function: SetBestGroups

   FAULT ->01012c07 8b4804     mov  ecx,[eax+0x4]   ds:0068e922=????????

CAUSE

This is caused by a problem in the SNA Server 3.0 Service Pack 1 TN3270 server, which was introduced by the addition of support for multiple ports.

STATUS

Microsoft has confirmed this to be a problem in SNA Server version 3.0 Service Pack 1. This problem was corrected in the latest SNA Server version 3.0 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

MORE INFORMATION

When this problem occurs, the stack back trace looks like the following:

   *----> Stack Back Trace <----*

   FramePtr ReturnAd Param#1  Param#2  Param#3  Param#4  Function Name
   0ca5fc10 01013e60 00183230 0ca5fc34 001849a2 001833c8
      tn3servr!SetBestGroups
   0ca5fc98 0100faa8 00183230 001849a2 0ca5fcbc 001849a2
      tn3servr!SRSGetSNAResourceFirst
   0ca5fd54 010184e3 00183230 001849a2 00183888 00000010
      tn3servr!SNAGenericSessionStart
   0ca5fd70 010179b7 00183230 00183230 0101704b 00183230
      tn3servr!TNTContinueDataFromNetwork
   0ca5fd7c 0101704b 00183230 0ca5ff5c 0ca5fe3c 00183230
      tn3servr!TNTContinueDataFromNetwork
   0ca5fd94 01018580 00183230 010152b2 00183230 00000011
      tn3servr!TNTContinueDataFromNetwork
   0ca5fd9c 010152b2 00183230 00000011 0ca5fe3c 001837cc
      tn3servr!TNTDataFromNetwork
   0ca5fe14 77f4f7c2 00000000 00000011 001837cc 7ffdf000 tn3servr!TCPRecv
   0ca5fe28 77fb03bb 01015100 001837cc 00000000 00010017
      kernel32!<nosymbols>
   0ca5ff5c 0100c876 00000003 0018d0b8 00000000 006ddcce ntdll!<nosymbols>

Keywords          : snatn3270 kbfix3.00.sp2 kbnetwork
Version           : 3.0
Platform          : winnt
Issue type        : kbbug
Solution Type     : kbfix