TPs Can't Be Invoked On Windows 95/NT Clients if One TP Ends

ID: Q180537

The information in this article applies to:

Microsoft SNA Server, versions 2.0, 2.1, 2.11, 2.11 SP1, 2.11 SP2, 3.0, 3.0 SP1, 3.0 SP2, 4.0

SYMPTOMS

If multiple instances of the same invokable APPC/CPI-C TP are running on a SNA Server Client for Windows 95 or Windows NT, the active TPs cannot be invoked if one instance of the TP ends for any reason.

SNA Server will log the following event in the Windows NT Application Event Log when attempting to invoke one of the remaining active TPs on the Windows 95 or Windows NT client:

Event ID: 60
Source: SNA Server
Description: Failed to invoke APPC TP <TP Name>, sense data = 084C0000

The 084C0000 refers to AP_TRANS_PGM_NOT_AVAIL_NO_RETRY.

CAUSE

When an invokable APPC TP is started on a client, SnaBase sends an update message to the client's sponsor SNA Server. The SNA Server adds the TP to its local service table; this entry is used for routing incoming DLOAD messages to the client. When the TP ends, the client SnaBase sends another update message to the sponsor server asking the SNA Server to remove the TP from its service table. These messages, both add and remove, are sent for each instance of the TP running on the client. The SNA Server only keeps one instance of the TP in its service table no matter how many instances are running on the client. When one instance of the TPs ends, the SNA Server marks the TP listed in the service table as inactive, which means none of the other TPs on the client can be invoked by the partner TP.

STATUS

Microsoft has confirmed this to be a problem in SNA Server version 2.0, 2.1, 2.11, 2.11 SP1, 2.11 SP2, 3.0, 3.0 SP1, 3.0 SP2, and 4.0.

This problem was corrected in the latest SNA Server versions 3.0 and 4.0 U.S. Service Packs. For information on obtaining these Service Packs, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K

A supported fix is now available for SNA Server 2.11 SP2, but has not been fully regression tested and should be applied only to systems experiencing this specific problem. Unless you are severely impacted by this specific problem, Microsoft recommends that you wait for the next Service Pack that contains this fix. Contact Microsoft Technical Support for more information.

MORE INFORMATION

With the fix applied, the SNA Server Clients for Windows 95 and Windows NT are updated so that the update message to remove a TP from the service table on the SNA Server is only sent after the last instance of the TP ends.

NOTE: There are other possible causes for this event, which are not related to this particular issue. For additional information, please see the following articles in the Microsoft Knowledge Base:

Q166623 SNA Server Rejects FMH-5 Attach Intended for TP on NT Client

Q170071 Invokable TP Timeout May Occur with Non-queued Operation

Additional query words:

Keywords : kbnetwork kbbug4.00 snaappc snacpic kbbug2.00 kbbug3.00 snaprog kbbug3.00.sp2 kbfix3.00.sp3 kbbug2.10 kbbug2.11 kbbug2.11.sp1 kbbug2.11.sp2 kbbug3.00.sp1 snatp snawin95 snawinnt
Version : WINDOWS:2.0,2.1,2.11,2.11 SP1,2.11 SP2,3.0,3.0 SP1,3.0 SP2,4.0
Platform : WINDOWS
Issue type : kbbug