ORA-20446: The owner of the job is not registered ORA-06512: at "SYSMAN.MGMT

Login as sysman user to the database and execute the following :

execute MGMT_USER.MAKE_EM_USER('ARCER');//标红处为需要导出导入权限的用户的用户名

备注:假如你没有开启SYSMAN用户，自行开启；