WORKFLOW RELATED :

to set the overrides from backend:

update fnd_svc_comp_param_vals
set    parameter_value = '&EnterEmailID'
where  parameter_id =
( select parameter_id
 from   fnd_svc_comp_params_tl
 where  display_name = 'Test Address');

TO SET THE OVERRIDE ADDRESS in WORKFLOW MAILER :

--Set the override address to  'xyz@abc.com' , using the following script:
--Login to the application server..
cd $FND_TOP/sql

@afsvcpup.sql

--Check the workflow services using the below query.
set pagesize 400
set linesize 120
set pagesize 50
column COMPONENT_NAME format a45
column STARTUP_MODE format a15
column COMPONENT_STATUS format a15
select fsc.COMPONENT_NAME,fsc.STARTUP_MODE,fsc.COMPONENT_STATUS
from APPS.FND_CONCURRENT_QUEUES_VL fcq, fnd_svc_components fsc
where fsc.concurrent_queue_id = fcq.concurrent_queue_id(+)
order by COMPONENT_STATUS , STARTUP_MODE , COMPONENT_NAME;