.NET Questions and Solutions

Symptoms
An application exception (trap) may occur on the SNA Server computer when you use the Rumba 5.2 TN5250 client to connect to the TN5250 Service. If you have Dr. Watson (Drwtsn32.exe) configured as the default debugger, a Drwtsn32.log file is created in the [NTROOT] directory. The following events are created in the Application event log of the Event Viewer:

Event ID: 5
Source : SNA TN5250 ServerDescription:
The SNA TN5250 Service detected an internal error.
File = ..\shared\tn5tnspm.c
Line = 3477
Fail = ((NB_IPS *)dsi5_data)->buf_size >= ((NB_IPS *)dsi5_data)->ips_length
Parm = 0×0
Event ID: 4097
Source: DrWatson
The application, exe\tn5250.dbg, generated an application error The error occurred on1/25/2000 @ 20:58: 3.406.
The exception generated was 80000003 at address 77f76274 (DbgBreakPoint).The following is an example of the exception in DbgBreakPoint:

Application exception occurred:App: exe\tn5250.dbg (pid=326)When: 1/25/2000 @ 20:58:3.406Exception number: 80000003 (hardcoded breakpoint)function: DbgBreakPointFAULT ->77f76274 ccint377f76275 c3ret77f76276 8bc0moveax,eax
Resolution
To resolve this problem, obtain the latest service pack for SNA Server 4.0. For additional information, click the following article number to view the article in theMicrosoft Knowledge Base:
215838?(http://support.microsoft.com/kb/215838/EN-US/) How to Obtain the Latest SNA Server Version 4.0 Service Pack

Symptoms
An application exception (trap) occurs in the SNA Server service(SNASERVR.EXE) when used with the Attachmate Extra! 3270 version 4.xemulator.
If you have Dr. Watson (DRWTSN32.EXE) configured as the default debugger,the DRWTSN32.LOG shows an exception similar to the following:

Application exception occurred:
App: snaservr.DBG (pid=147)
When: 8/1/1995 @ 16:39:1.590
Exception number: c0000005 (access violation)In addition, SNA Server logs Event 624 in the Windows NT Application Log(as seen in the Event Viewer) when this trap occurs. The following is adetailed description of the Event 624 that is logged when this trap occurs:

Creating dump file C:\SNA\TRACES\SNADUMP.LOG for SNASERVR.EXE
EXPLANATION
A process (SNASERVR.EXE) ended abnormally due to a protection
violation or similar condition and a dump file SNADUMP.LOG has been
created that contains information about the state of the process at
the time of the exception. Register information is contained in your
Windows NT root directory in the file DRWTSN32.LOG.
Resolution
A 3270 emulator has two connections to the SNA Server service. Oneconnection is for SSCP-LU data and the other one is for PLU-SLU (PrimaryLogical Unit – Secondary Logical Unit) data. The SNA Server service trap iscaused because the 3270 emulator is sending a PLU-SLU message on theconnection that is only meant to handle SSCP-LU data. This is behaviorwhich the SNA Server service is not expecting, and it traps when itaccesses its session control block for the SSCP-LU session and treats it asa control block for the PLU-SLU session.

Symptoms
The SNA Server Manage Agent service (MngAgent.exe) may generate anapplication exception when stopping an LU. When this problemoccurs, theWindows NT Application Event Log contains a message similar to thefollowing:

Event ID: 624Source: SNA ServerDescription: Creating dump file C:\SNA\traces\snadump.log formngagent.exe.If Drwtsn32.exe is the default debugger on the Windows NT Servercomputer that is running SNA Server, an entry similar to the following willbe included in the Drwtsn32.log in the Windows NT directory:

Application exception occurred:App: exe\mngagent.dbg (pid=250)When: 5/20/1998 @ 8:18:57.93Exception number: c0000005 (access violation)(…)function: CSISend614846d6 50pusheax614846d7 ff1588104861ds:61481088=77f02df5calldword ptr[_imp__LocalLock(61481088)]614846dd 8b542414movedx,[esp+0x14]ss:035de73b=????????614846e1 8b5204movedx,[edx+0x4]ds:05873cd2=????????614846e4 66897204mov[edx+0x4],sids:05873cd3=????614846e8 8b4d0cmovecx,[ebp+0xc]ss:01508676=????????614846eb 8bf0movesi,eax614846ed 8bc1moveax,ecx614846ef 8d7a09leaedi,[edx+0x9]ds:05873cd2=????????614846f2 c1e902shrecx,0×2FAULT -<614846f5 f3a5repmovsdds:00114000=????????es:044552e5=0004001a614846f7 8bc8movecx,eax614846f9 83e103andecx,0×3614846fc f3a4repmovsbds:00114000=??es:044552e5=1a614846fe 668b4d0cmovcx,[ebp+0xc]ss:01508677=????61484702 66894a06mov[edx+0x6],cxds:05873cd3=????61484706 8b5508movedx,[ebp+0x8]ss:01508676=????????61484709 52pushedx6148470a ff1560104861ds:61481060=77f02d13calldword ptr[_imp__LocalUnlock(61481060)]61484710 8a4322moval,[ebx+0x22]ds:0150a0d6=??61484713 8d4c2424leaecx,[esp+0x24]ss:035de73b=????????61484717 fec0incal*—-< Stack Back Trace >—-*FramePtr ReturnAd Param#1Param#2Param#3Param#4Function Name021bfd4c 6148452f 000eb6d0 000e9c70 00113ffc 000eb6d0 snamanag!CSISend(FPO: [EBP 0x000eb6d0] [2,3,4])021bfd60 61481996 000eb6d0 07087fff 0000050a 00113ff0snamanag!CSIPreQueue(FPO: [9,0,2])021bff38 60b0530c 040805c4 00252d00 00000004 6098a984snamanag!SNAStopService(FPO: [EBP 0xffffffff] [1,104,4])021bff48 6098a984 021bff58 00252d00 002bf670 0000064emngsna!CDispLUServe::OnCommand(FPO: [1,1,1])021bff64 6098a84d 77e71b04 6098a800 77e719c8 60b045fbmngbase!CNotifyQueue::Dispatch(FPO: [0,4,1])021bff74 60b045fb ffffffff 7ffdf000 0111ffb8 021bffecmngbase!CNotifyQueue::ProcessWait(FPO: [1,0,3])021bffb8 77f04f2c 00000000 7ffdf000 0111ffb8 00000000 mngsna!DoMngSna(FPO: [EBP 0x7ffdf000] [1,11,4])7ffdf000 ffffffff 01000000 000805c0 00020000 00000000kernel32!lstrcmpiW00010000 0050004d 00540055 00520045 0041004e 0045004drpcrt4!<nosymbols>
Resolution
SNA Server 3.0To resolve this problem, obtain the latest service pack for SNA Server version 3.0. For additional information, click the following article number to view the article in theMicrosoft Knowledge Base:
184307?(http://support.microsoft.com/kb/184307/EN-US/) How to Obtain the Latest SNA Server Version 3.0 Service Pack
SNA Server 4.0This problem was corrected in the latest Microsoft SNA Serverversion 4.0 U.S. Service Pack. For information on obtaining this Service Pack,query on the following word in the Microsoft Knowledge Base (without thespaces):

S E R V P A C K

Symptoms
When you are running an Advanced Program-to-Program Communications (APPC) or Common Programming Interface for Communications (CPI-C) application, you may encounter an Access Violation (AV) in DMODInitReceiveAllocate.
If Dr. Watson is configured as the default debugger, an entry similar to the following may be appended to the Drwtsn32.log file:

function: DMODInitReceiveAlloc6721a1c4 8d54d034leaedx,[eax+edx*8+0x34]ds:040cbeef=????????6721a1c8 83c9fforecx,0xff6721a1cb 33c0xoreax,eax6721a1cd f2aerepnescasbes:02ced4e8=??6721a1cf f7d1notecx6721a1d1 2bf9subedi,ecx6721a1d3 8bc1moveax,ecx6721a1d5 8bf7movesi,edi6721a1d7 8bfamovedi,edx6721a1d9 c1e902shrecx,0×2FAULT ->6721a1dc f3a5repmovsd ds:0284f79c=20202020 es:02ced4e8=????????6721a1de 8bc8movecx,eax6721a1e0 83e103andecx,0×36721a1e3 f3a4repmovsbds:0284f79c=20 es:02ced4e8=??6721a1e5 33c0xoreax,eax6721a1e7 8b7dc4movedi,[ebp-0x3c]ss:03c2e26e=????????6721a1ea 668b4704movax,[edi+0x4]ds:040cbeef=????6721a1ee 8d0c40leaecx,[eax+eax*2]ds:0000001b=????????6721a1f1 c1e103shlecx,0×36721a1f4 2bc8subecx,eax6721a1f6 8bb548ffffffmovesi,[ebp+0xffffff48]ss:0284f7b0=02cc025c6721a1fc c744ce1004000000ds:013dea0d=????????movdword ptr [esi+ecx*8+0x10],0×4*—-> Stack Back Trace <—-*FramePtr ReturnAd Param#1Param#2Param#3Param#4Function Name0284f868 63404de3 62e1b5b0 00000001 00a9a4bc 00a9a4d8 snadmod!DMODInitReceiveAlloc (FPO: Non-FPO [5,128,3])0284f89c 63403254 00000000 63401bb6 0284fa0c 0f7e0000 wappc32!receive_allocate_proc(FPO: [EBP 0x00014000] [0,3,4])0284f8a4 63401bb6 0284fa0c 0f7e0000 00000000 77f674c0 wappc32!ps_verb_router(FPO: [0,0,1])0284f9bc 63401737 0f7e0000 00000002 62e018a0 00000000 wappc32!Appc_Main(FPO: [EBP 0x0284fa0c] [4,65,4])
Resolution
The application exception is caused by a buffer overrun during Dynamic Load processing.