IBM PCOM 5250 Fails on Windows 95/98 after a 3270/FMI Session Is Closed

ID: Q247332

The information in this article applies to:

Microsoft SNA Server, versions 3.0 (all SP), 4.0, 4.0 SP1, 4.0 SP2, 4.0 SP3

SYMPTOMS

When you use IBM Personal Communications (version 4.3) with the SNA 4.0 Windows 95/98 client software or with the SNA 4.0 Windows NT client software, a 5250 session stops responding or fails with a page fault after a 3270 session is closed. For example:

PCSCM caused an invalid page fault in module WAPPC32.DLL at 015f:6340e645

The offset may vary depending on the version of the SNA Windows 95/98 or Windows NT client software being used.

CAUSE

If an application supports both a 3270/FMI session and an APPC or CPIC conversation from the same process, and closes the 3270/FMI session by calling the sbputerm() function, the SNA client incorrectly frees the SNADMOD client code while the APPC/CPIC application is still active.

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 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	Platform
Snadmod.dll	11/29/99	5:24p	Windows 95/98
Snadmod.dll	12/13/99	x:xxx	Windows NT

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

WORKAROUND

To work around this problem, do not close the 3270 session if an APPC conversation is still active, or close the APPC conversation before the 3270 session is closed.

STATUS

Microsoft has confirmed this to be a problem in Microsoft SNA Server version 3.0, 4.0, 4.0 SP1, 4.0 SP2 and 4.0 SP3.

Additional query words:

Keywords :
Version : WINDOWS:3.0 (all SP),4.0,4.0 SP1,4.0 SP2,4.0 SP3
Platform : WINDOWS
Issue type : kbbug