ORA-12516: TNS:LISTENER COULD NOT FIND AVAILABLE HANDLER WITH MATCHING PROTOCOL STACK

Dear Friends,

Below are steps for ORA-12516: TNS:LISTENER COULD NOT FIND AVAILABLE HANDLER WITH MATCHING PROTOCOL STACK error

ERROR : ORA-12516: TNS:listener could not find available handler with matching protocol stack

CAUSE : Its Reached maximum process.

SOLUTION : 

Check maximum value for processes and sessions

select name, value from v$parameter where name in (‘processes’,’sessions’);

Check current process and session and maximum limitation

select * from v$resource_limit;

Increase your process and session, for example to 800

alter system set processes=800 scope=spfile;

alter system set sessions=885 scope=spfile;

Restart the Database with below commands,

shutdown immediate;

and 

startup;

or 

startup force ;

all changes will effected permanently.