APEX Images not rendered after refresh

We have refreshed one of our database which is being used by apex applications.We used to store most of the images in the file system.Some of the images are being stored in database.After refresh,when we tried to access application ,apex images which are stored in database is not displayed .

Solution :

We need to reset the password (as same as before refresh) and unlock the below user accounts.

APEX_PUBLIC_USER
APEX_REST_PUBLIC_USER
APEX_LISTENER

How to send email from APEX?

Command to Send EMail:

DECLARE
 l_id number;
BEGIN
    l_id := APEX_MAIL.SEND (p_to        => 'srm.jay@gmail.edu',  
                            p_from      => 'srm.jay@stanford.edu',  
                            p_subj      => 'APEX_MAIL from imguat',
                            p_body      => 'Please review the attachment.',
                            p_body_html => '<b>Please</b> review the attachment');    
COMMIT;
END;
/

To send a mail immediately from the apex mail queue:

Oracle Application Express logs successfully submitted message in the table APEX_MAIL_LOG with the timestamp reflecting your server's local time. 

begin
APEX_MAIL.PUSH_QUEUE('localhost','25');
end;
/

Please check the apex_mail_log table for any errors or warnings.

select mail_send_error from APEX_MAIL_LOG ;