3270 Print Session Stays in Spooling Status

• Microsoft SNA Server, version 3.0

SYMPTOMS

A 3270 print session defined for the SNA Server 3.0 Host Print Service may stay in a spooling state after a host print job is sent to the printer. The result of this is that the print job does not finish printing completely.

CAUSE

The credit mechanism used by the FMI interface to provide flow control between SNA Server and an application (to prevent the application from exhausting its resources) does not correctly handle a BID message. A BID message received from the host is counted for pacing purposes, but not for credit purposes. The default credit algorithm fails to send a credit message from the Print Server service to the SNA Server service. Because the SNA Server service did not receive a credit message, it cannot send a pacing response to the host. This causes the host to stop sending data to SNA Server for the print session, causing the print session to remain in a spooling state. Therefore, the print job does not finish printing.

RESOLUTION

To work around this problem, obtain the hotfix mentioned below. With the hotfix, the 3270 Print Provider has been updated to correct this problem. This update allows a single credit message to be sent to the SNA Server service for all data messages it receives. The updated module is:

   <Snaroot>\System\3270ppd.dll

STATUS

Microsoft has confirmed this to be a problem in SNA Server version 3.0. This problem was corrected in the latest Microsoft SNA Server 3.0 U.S. Service Pack. For information on obtaining the service pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

   S E R V P A C K