Concurrent Managers Status show “Target node/queue unavailable

Solution:

Ensure Database is Running and Middle Tier Services are down.

Connect SQLPLUS as APPS user and run the following :

sql> EXEC FND_CONC_CLONE.SETUP_CLEAN;

sql> COMMIT;


Run AutoConfig on all tiers, firstly on the DB tier and then the APPS tiers and webtier to repopulate the required systemtables
Run the CMCLEAN.SQL script from the referenced note below (don’t forget to commit).
Note.134007.1 – ‘CMCLEAN.SQL – Non Destructive Script to Clean Concurrent  Manager Tables‘
Start the middle tier services including your concurrent manager.
Retest the issue.