I am a beginner to the Joomla,after install the website,I can't get into the admin page.
The Joomla shows:

An error has occurred while processing your request.

You may not be able to visit this page because of:

    an out-of-date bookmark/favourite
    a mistyped address
    a search engine that has an out-of-date listing for this site
    you have no access to this page

Go to the Home Page

Here's my web server infomation:

[Web Server ] Mar 29 19:36:33 |INFO   | SERVER GET  (200) /installation/template/images/select-bg.svg 
[Web Server ] Mar 29 19:37:04 |INFO   | SERVER POST (200) /installation/index.php?task=installation.dbcheck&format=json host="127.0.0.1:8004" scheme="https"
[Web Server ] Mar 29 19:37:06 |INFO   | SERVER POST (200) /installation/index.php?task=installation.create&format=json 
[Web Server ] Mar 29 19:37:55 |INFO   | SERVER POST (200) /installation/index.php?task=installation.populate1&format=json 
[Web Server ] Mar 29 19:38:13 |INFO   | SERVER POST (200) /installation/index.php?task=installation.populate2&format=json 
[Web Server ] Mar 29 19:38:29 |INFO   | SERVER POST (200) /installation/index.php?task=installation.populate3&format=json 
[Web Server ] Mar 29 19:38:29 |INFO   | SERVER POST (200) /installation/index.php?task=installation.custom1&format=json 
[Web Server ] Mar 29 19:38:29 |INFO   | SERVER POST (200) /installation/index.php?task=installation.custom2&format=json 
[Web Server ] Mar 29 19:38:55 |INFO   | SERVER POST (200) /installation/index.php?task=installation.config&format=json 
[Web Server ] Mar 29 19:39:00 |INFO   | SERVER GET  (200) /installation/index.php?view=remove&layout=default 
[Web Server ] Mar 29 19:39:01 |INFO   | SERVER GET  (200) /installation/template/css/template.min.css?b85d5e1d734b6f6523f68c105d691f4d 
[Web Server ] Mar 29 19:39:01 |INFO   | SERVER GET  (200) /installation/template/js/template.js?b85d5e1d734b6f6523f68c105d691f4d 
[Web Server ] Mar 29 19:39:01 |INFO   | SERVER GET  (200) /installation/template/js/remove.js?b85d5e1d734b6f6523f68c105d691f4d 
[Web Server ] Mar 29 19:39:23 |INFO   | SERVER POST (200) /installation/index.php?task=installation.removeFolder&format=json host="127.0.0.1:8004" scheme="https"
[Web Server ] Mar 29 19:39:23 |WARN   | SERVER GET  (404) /administrator/ 
[Web Server ] Mar 29 19:39:23 |INFO   | SERVER GET  (200) /media/system/css/joomla-fontawesome.min.css 
[Web Server ] Mar 29 19:44:54 |INFO   | SERVER GET  (200) / 
[Web Server ] Mar 29 19:44:54 |INFO   | SERVER GET  (200) /media/templates/site/cassiopeia/css/global/colors_standard.min.css?2c60246a50e86efa455be00cd42aee0a 
[Web Server ] Mar 29 19:44:54 |INFO   | SERVER GET  (200) /media/templates/site/cassiopeia/js/template.min.js?2c60246a50e86efa455be00cd42aee0a 
[Web Server ] Mar 29 19:44:54 |INFO   | SERVER GET  (200) /media/templates/site/cassiopeia/css/template.min.css?2c60246a50e86efa455be00cd42aee0a 
[Web Server ] Mar 29 19:44:54 |INFO   | SERVER GET  (200) /media/system/css/joomla-fontawesome.min.css?2c60246a50e86efa455be00cd42aee0a 
[Web Server ] Mar 29 19:45:01 |INFO   | SERVER POST (303) /index.php host="127.0.0.1:8004" scheme="https"
[Web Server ] Mar 29 19:45:01 |INFO   | SERVER GET  (200) / 
[Web Server ] Mar 29 19:45:02 |INFO   | SERVER POST (303) /index.php host="127.0.0.1:8004" scheme="https"
[Web Server ] Mar 29 19:45:03 |INFO   | SERVER GET  (200) / 
[Web Server ] Mar 29 19:45:10 |INFO   | SERVER POST (303) /index.php host="127.0.0.1:8004" scheme="https"
[Web Server ] Mar 29 19:45:11 |INFO   | SERVER GET  (200) / 
[Web Server ] Mar 29 19:45:31 |WARN   | SERVER GET  (404) /administrator