Q314973: "Unable to Write File" Err Msg After Adding Local APPC LU

Article: Q314973
Product(s): Microsoft SNA Server
Version(s): 4.0,4.0 SP1,4.0 SP2,4.0 SP3,4.0 SP4
Operating System(s): 
Keyword(s): kbDSupport sna4 kbsna400sp1 kbsna400sp2 kbsna400sp3 kbhis2000 kbhis2000bug kbsna400sp4
Last Modified: 08-MAY-2002

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The information in this article applies to:

- Microsoft SNA Server, versions 4.0, 4.0 SP1, 4.0 SP2, 4.0 SP3, 4.0 SP4 
- Microsoft Host Integration Server 2000 
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SYMPTOMS
========

If you try to save an SNA Server or Host Integration Server (HIS) 2000
configuration file (Com.cfg) after you add local Advanced Program-to-Program
Communications (APPC) logical units (LUs), an "Unable to write file" error
occurs.

The new local APPC LUs that you added are not saved in the configuration.

This is only likely to occur with very large SNA Server or HIS 2000
configurations. The following list includes some configuration parameters that
increase the chance that this problem will occur:

- There are more than 2,000 local APPC LUs.

- "Implicit Incoming Remote LU" is configured for the local APPC LUs.

- "Implicit Incoming Mode" is configured for the remote APPC LUs.

CAUSE
=====

The SNA Server or HIS 2000 configuration dynamic link library (DLL) incorrectly
exceeds the maximum value for the number of internal records that are needed
when you save large configuration files. This results in the "Unable to write
file" error when you save the configuration.


RESOLUTION
==========

SNA Server 4.0:

A supported fix is now available from Microsoft, but it is only intended to
correct the problem described in this article and should be applied only to
systems experiencing this specific problem. This fix may receive additional
testing at a later time, to further ensure product quality. Therefore, if you
are not severely affected by this problem, Microsoft recommends that you wait
for the next Microsoft SNA Server version 4.0 service pack 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 about support costs, please go to the following
address on the World Wide Web:

  http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS

NOTE: In special cases, charges that are normally incurred for support calls may
be canceled, if a Microsoft Support Professional determines that a specific
update will resolve your problem. Normal support costs will apply to additional
support questions and issues that do not qualify for the specific update in
question.

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

+--------------------------------+
| File name  | Date       | Time | 
+--------------------------------+
| Snacfg.dll | 12/18/2001 | 7:39 | 
+--------------------------------+

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



Host Integration Server 2000:

No fix is yet available for this problem in Host Integration Server 2000.

STATUS
======

SNA Server 4.0:

Microsoft has confirmed this to be a problem in Microsoft SNA Server versions
4.0, 4.0 Service Pack (SP) 1, 4.0 SP2, 4.0 SP3, and 4.0 SP4.

Host Integration Server 2000:

Microsoft has confirmed this to be a problem in Microsoft Host Integration Server
2000.



MORE INFORMATION
================

SNA Server 4.0 and HIS 2000 support a maximum of 3,000 local APPC LUs per SNA
Server service.

For additional information on problems that can cause an "Unable to write file"
error when you save an SNA configuration file, click the article number below to
view the article in the Microsoft Knowledge Base:

  Q293879 Unable to Write File Error After Changing Com.cfg

Additional query words:

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Keywords          : kbDSupport sna4 kbsna400sp1 kbsna400sp2 kbsna400sp3 kbhis2000 kbhis2000bug kbsna400sp4 
Technology        : kbAudDeveloper kbSNAServSearch kbHostIntegServ2000 kbSNAServ400 kbSNAServ400SP1 kbSNAServ400SP2 kbSNAServ400SP3 kbSNAServ400SP4
Version           : :4.0,4.0 SP1,4.0 SP2,4.0 SP3,4.0 SP4
Issue type        : kbbug
Solution Type     : kbfix

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