How do I do manually run a job and where are any errors listed in oracle

last run jobs will be at the top running the below command:
select * from all_jobs order by job desc;

run the job:
BEGIN
DBMS_JOB.RUN(79474);
END;
errors show up in the alert log file (located in $ORACLE_HOME/admin/$ORACLE_SID/bdump).

alert log was here for one site for instance: D:\oracle\product\10.2.0\admin\IM\bdump\alert_im.log