custom timer job not applicable ignoring job definition

We have created custom timer job in share point 2010.but we are getting error

job definition "Job defination name", id ed6b4720-67c3-4bbc-aa46-e98a2aa67202 not applicable, ignoring

We are unable to find out error for the same in share point log.

Its webapplication level timer job . and farm architecture is 2 WFE and 1 application server.