Thank you for all these advice. But when I finished the steps that you mentioned, as well as followed the ((https://wackowiki.org/doc/Doc/%E7%AE%80%E4%BD%93%E4%B8%AD%E6%96%87/%E7%AE%A1%E7%90%86%E9%9D%A2%E6%9D%BF this configuration)) I still can't access the admin page. I just get a notify that the administrative password specified. Note: lack of an admin password is a security threat! Enter the password in the configuration file and run the program again.
The most important thing is how could I reset my previous admin account's password after I followed these steps? I hope I can restart to login my previous admin account. Thank you.