Executing application instance certification job failed

I am newbie to OIM (11.1.2.3.0).  I was trying to create application instance certification so after reading oracle documentation, I followed below steps.

1. logged in as an user "A" to OIM Identity self service.

2. created an application instance type certification definition called "bar" from Compliance > Identity Certification > Definitions (NOTE: There is an existing application instance called "foo").

3. went through phases of base selection, content selection, configuration, reviewers, incremental and summary.

4. I have to note that I selected Accounts of selected users under Content Selection, then added an internal user "B" (NOTE: I have no clue if there is any relation between the user B and application instance foo I selected).