TN3270 Server Access Violation in Mngext!MngDeleteObject()

ID: Q245453

The information in this article applies to:

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

SYMPTOMS

The SNA Server TN3270 Server process (Tn3servr.exe) may fail unexpectedly with an access violation in routine mngext!MngDeleteObject. If Drwtsn32.exe is configured as the default debugger, a Drwtsn32.log file will be created and will include the following failure information:


Application exception occurred:
        App: exe\tn3servr.dbg (pid=process id)
        When: (date and time)
        Exception number: c0000005 (access violation)

[...]

State Dump for Thread Id (thread)

eax=00000000 ebx=00000000 ecx=00000000 edx=0ca40440 esi=0c9fff98 edi=00243160
eip=60a01dd7 esp=0c9fff78 ebp=77f67500 iopl=0         nv up ei pl zr na po nc
cs=001b  ss=0023  ds=0023  es=0023  fs=0038  gs=0000             efl=00000246

function: MngDeleteObject
        60a01db8 59               pop     ecx
        60a01db9 c20800           ret     0x8
        60a01dbc 6a00             push    0x0
        60a01dbe 8d44240c         lea     eax,[esp+0xc]
        60a01dc2 6a00             push    0x0
        60a01dc4 50               push    eax
        60a01dc5 8bcf             mov     ecx,edi
        60a01dc7 c70600000000     mov     dword ptr [esi],0x0
        60a01dcd ff15d010a060 
                   call    dword ptr [_imp_?GetNotify (60a010d0)]
        60a01dd3 8b4c2408         mov     ecx,[esp+0x8]          
FAULT ->60a01dd7 8b11             mov     edx,[ecx] 
        60a01dd9 ff5220           call    dword ptr [edx+0x20]   
        60a01ddc 5f               pop     edi
        60a01ddd 5e               pop     esi
        60a01dde 59               pop     ecx
        60a01ddf c20800           ret     0x8

*---- Stack Back Trace ----*

FramePtr ReturnAd Param#1  Param#2  Param#3  Param#4  Function Name
77f67500 8b000000 83042454 7500147a 42ff904f 8b197504 mngext!MngDeleteObject

CAUSE

The management status reporting interface running underneath the TN3270 server was attempting to delete an object after it had already been freed, causing an access violation.

RESOLUTION

A supported fix that corrects this problem is now available from Microsoft, but it has not been fully regression tested and should be applied only to systems experiencing this specific problem. If you are not severely affected by this specific problem, Microsoft recommends that you wait for the next Microsoft SNA Server 4.0 service pack (4) that contains this fix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web:

http://www.microsoft.com/support/supportnet/overview/overview.asp

The English version of this fix should have the following file attributes or later:

File name	Date	Time
MNGEXT.DLL	10/18/99	02:49p

NOTE: Because of file dependencies, the most recent fix that contains the above files may also contain additional files.

NOTE: If this product was already installed on your computer when you purchased it from the Original Equipment Manufacturer (OEM) and you need this fix, please call the Pay Per Incident number listed on the above Web site. If you contact Microsoft to obtain this fix, and if it is determined that you only require the fix you requested, no fee will be charged. However, if you request additional technical support, and if your no-charge technical support period has expired, or if you are not eligible for standard no-charge technical support, you may be charged a non-refundable fee.

For more information about eligibility for no-charge technical support, see the following article in the Microsoft Knowledge Base:

Q154871 Determining If You Are Eligible for No-Charge Technical Support

WORKAROUND

A fix for a similar problem is already present in SNA Server 3.0 Service Pack 3 and Service Pack 4.

STATUS

Microsoft has confirmed this to be a problem in SNA Server 4.0 Service Pack 1, Service Pack 2, and Service Pack 3.

Additional query words:

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