Out of sudden, you screen keep prompting below notification while logging to Oracle using SQLplus.
sqlplus / as sysdba SQL*Plus: Release 10.2.0.5.0 - Production on Tue Apr 3 23:44:53 2014 Copyright (c) 1982, 2008, Oracle. All rights reserved. ERROR: ORA-12518: TNS:listener could not hand off client connection
Solution
Determine the current value of PROCESSES parameter.
SHOW PARAMETER PROCESSES
Increase the parameter value (below example is for spfile)
ALTER SYSTEM SET PROCESSES=NEW_VALUE SCOPE=spfile
