Message Oracle TNS-04012 - Unable to start Oracle Connection Manager instance.

ERRORUnable to start Oracle Connection Manager instance.
CAUSECMCTL was unable to start the Oracle Connection Manager instance. Some of the possible reasons include: cmadmin not present in ORACLE_HOME/bin, Invalid parameter in configuration repository, wrong parameter values, or log directory not present.
ACTION1. Check whether log directory is present, and is writable. Log directory can be found at ORACLE_HOME/network/log, or as specified by the LOG_DIRECTORY parameter in CMAN.ORA. 2. Turn on logging or tracing to get more information about this error. 3. Correct any parameter errors (or mismatched paranthesis), and retry starting Oracle Connection Manager. 4. If the problem persists, contact Oracle Support Services.