Output Post-processor actions failed issues in EBS R12

Environment:
Oracle EBS 12.1.3, Oracle Database 11gR2, RedHat Linux 5

Symptoms:
1) Users unable to open the out files.
2) Concurrent requests failed with “Post-processing of request failed error message”
3) One or more post-processing actions failed. Consult the OPP service log for details.
4) No further attempts will be made to post-process this request.


Cause:
The concurrent manager process was able to successfully invoke the Output Post-Processor (OPP) but encountered a timeout as the OPP takes longer than the value assigned to complete the job.


 Solution:
1) Increase the value of profile Concurrent: OPP Response Timeout . Bounce Apache and retest.
2) If the issue still exists, perform the following steps.
3) Increase the number of Output Post Processors as follows:
4) Increase the number of processes for Output Post Processor.

Additionally, ensure there is a setting of  oracle.apps.fnd.cp.opp.OPPServiceThread:2:0:max_threads=5 under Parameters.