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Q294393: Error "No LU in LU Group Free" Occurs When Starting 3270 Applet

Article: Q294393
Product(s): Microsoft SNA Server
Version(s): 3.0 SP2,3.0 SP3,3.0 SP4,4.0,4.0 SP1,4.0 SP2,4.0 SP3,4.0 SP4
Operating System(s): 
Keyword(s): kbDSupport
Last Modified: 17-OCT-2001

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The information in this article applies to:

- Microsoft SNA Server, versions 3.0 SP2, 3.0 SP3, 3.0 SP4, 4.0, 4.0 SP1, 4.0 SP2, 4.0 SP3, 4.0 SP4 
- Microsoft Host Integration Server 2000 
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SYMPTOMS
========

When the 3270 client is started, the error message "No LU in LU Group Free"
appears.

CAUSE
=====

In this case, SNA Server/Host Integration Server 2000 is working as designed.
The error is caused by the application's Associated Printer LU (logical unit)
feature. All display LUs are associated with a corresponding printer LU. Because
all of the printer LUs are connected successfully to printer sessions, the
associated LU feature blocks the connection to the associated display LU, and
the "No LU in LU Group Free" message is returned.

NOTE: This error message may also appear if there are no LUs available, which is
an unrelated issue.

RESOLUTION
==========

To resolve the problem, disassociate the printer LUs from the display LUs and
save the Com.cfg file.

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

Beginning with SNA Server 3.0 Service Pack 2 (SP2), the SNA Server does not
allow a user to open a 3270 display LU if its associated printer is in use by
another user. For additional information, click the article number below to view
the article in the Microsoft Knowledge Base:

  Q172637 User Able to Open Display Session If Associated Printer in Use

Users who have host applications with direct relationships between display LUs
and printer LUs can associate printers with the display LUs. The associated
printer feature, however, was designed for 3270 print emulators only and not for
SNA Server print service sessions.

For additional information, see the following:

  Chapter 3 of the Administration Guide. The Administration Guide is included
  with the Software Development Kit (SDK), which you must select to install
  during setup.

  Q172637 User Able to Open Display Session If Associated Printer in Use

  Q195063 Common User ID Problem When Using Associated Printer Feature

Additional query words:

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Keywords          : kbDSupport 
Technology        : kbAudDeveloper kbSNAServSearch kbHostIntegServ2000 kbSNAServ400 kbSNAServ300SP3 kbSNAServ400SP1 kbSNAServ400SP2 kbSNAServ400SP3 kbSNAServ400SP4 kbSNAServ300SP2 kbSNAServ300SP4
Version           : :3.0 SP2,3.0 SP3,3.0 SP4,4.0,4.0 SP1,4.0 SP2,4.0 SP3,4.0 SP4

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