Did you try De-activating the Workflow mailer service, then activating back again.
Please run again the cmclean script and check.
- Shutdown CM
- Run cmclean.
- Start CM.
If still the issue persist, please check the workflow mailer log file for more information.
Plz check Concurren> manager> administer>Workflow mailer service> processes> status
it should be active if not
if it is initializing then kill the process and bounce the CM.
Please post the details of the application release, database version and OS.
As mentioned above, please check Workflow log file for details about the error.
11i-12 Workflow Java Mailer & Notifications FAQ (Doc ID 562551.1)
11i - 12 How To Troubleshoot Java-based Workflow Notification Mailer (Doc ID 242941.1)
Oracle Workflow Release 12 Diagnostics (Doc ID 469822.1)
WF H Diagnostics, Solutions and Information (Doc ID 332152.1)