pdf file not created

Hi,

Our sales order acknowledgement program produces xml output and create a pdf(using a template created by BI Publisher).  However, for one cancelled soa, we get no output.

from the log file:

+------------- 1) PUBLISH -------------+
Beginning post-processing of request 21053957 on node OAPMTFW03 at 22-NOV-2010 13:05:55.
Post-processing of request 21053957 failed at 22-NOV-2010 13:05:55 with the error message:
One or more post-processing actions failed. Consult the OPP service log for details.
+--------------------------------------+

+------------- 2) PRINT   -------------+
Not printing the output of this request because post-processing failed.
+--------------------------------------+


there is xml produced however.  any ideas?