Grant ACL to user for sending mail

Step – 1 :: create ACL scrip change “principal” name(Schema/User name).

begin
  dbms_network_acl_admin.create_acl(
    acl         => 'utl_smtp.xml',
    description => 'Allow mail to be send',
    principal   => 'USER',
    is_grant    => TRUE,
    privilege   => 'connect'
    );
    commit;
end;

Step – 2::
begin
  dbms_network_acl_admin.add_privilege (
  acl       => 'utl_smtp.xml',
  principal => 'USER',
  is_grant  => TRUE,
  privilege => 'connect'
  );
  commit;
end;

Step - 3 ::
begin
  dbms_network_acl_admin.assign_acl(
  acl  => 'utl_smtp.xml',
  host => '12.345.67.89',
  lower_port => 25,
  upper_port => 25
  );
  commit;
end;