DOCUMENT:Q173398  13-JUN-2001  [sna]
TITLE   :SNA Win 3.x Application Fails over WinNT Client Thunking DLLs
PRODUCT :Microsoft SNA Server
PROD/VER:WINDOWS:2.11 (all SP),3.0 (all SP)
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft SNA Server, versions 2.11 SP1, 2.11 SP2, 3.0 SP1, 3.0 SP2, 3.0 SP3, 3.0 SP4 
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SYMPTOMS
========

An SNA Server 16-bit Windows application fails to work over the SNA Server
Windows NT client software configured with the 16-bit to 32-bit SNA API thunking
DLLs. However, the same application works fine over the SNA Server Windows 3.x
client software.

The following errors messages may appear only when you run the Windows
application over the following SNA API thunking DLLs:

 - If the APPC API is being used (over Winappc.dll), TP_STARTED fails with:

   primary_rc = 0xF004 (AP_COMM_SUBSYSTEM_NOT_LOADED)
   secondary_rc = 0xCCCCCCCC (undefined)

 - If the CPIC API is being used (over Wincpic.dll), any CPIC function fails
   with Error 20 (CM_PRODUCT_SPECIFIC_ERROR). Note that this error can also be
   due to other problems documented in Knowledge Base article Q132720.

 - If the LUA RUI or SLI API is being used (over Winrui.dll or Winsli.dll), the
   following error message displays:

   primary_rc = 0xF004 (LUA_COMM_SUBSYSTEM_NOT_LOADED)
   secondary_rc = 0xFFFFFFFF (undefined)

 - If the Common Service Verb API is being used (over Wincsv.dll), the following
   error message displays:

   primary_rc = 0xF004 (LUA_COMM_SUBSYSTEM_NOT_LOADED)
   secondary_rc = 0xFFFFFFFF (undefined)

For instructions on how to enable the 16-bit to 32-bit SNA API thunking DLLs, see
the following Knowledge Base article:

   Q107571 Running SNA Server Win16, OS/2, or MS-DOS Applications

CAUSE
=====

When running over the SNA Server Windows NT client thunking DLLs, the 16-bit
Windows application must first initialize the API interface by calling the
appropriate WinXXXXStartup call before attempting to use any function. The
thunking DLL initializes the Snahlp32.dll and 32-bit SNA API DLLs (Wappc32.dll,
Wcpic32.dll, Winrui32.dll, Winsli32.dll, and Wincsv32.dll) only after the
appropriate WinXXXXStartup function has been called.

Refer to the relevant SNA Server API programmer's guide for a description of
WinAPPCStartup, WinCPICStartup, WinRUIStartup, WinSLIStartup, and WinCSVStartup
calls. Each API reference states the requirement to call this function first, in
order to initialize the API interface.

RESOLUTION
==========

The 16-bit Windows application should be modified so that the appropriate
WinXXXXStartup call is issued before using any API function supported by that
interface.

Additional query words: win16 win3x thunk

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Keywords          :  
Technology        : kbAudDeveloper kbSNAServSearch kbSNAServ211SP1 kbSNAServ211SP2 kbSNAServ300SP3 kbSNAServ300SP1 kbSNAServ300SP2 kbSNAServ300SP4
Version           : WINDOWS:2.11 (all SP),3.0 (all SP)
Issue type        : kbprb

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