A 404 page refers to the page that a user sees when trying to access a non-existent page on the website (because the user clicked a damaged link, the page has been deleted, or the user entered the wrong URL). When the user attempts to enter such a non-existent page, the IIS web server will return a 404 HTTP status code by default, indicating that the page has not been found.
The purpose of a 404 page is to tell visitors that the page they requested does not exist or that the link is wrong, and at the same time guides users to use other pages of the website instead of closing the window and leaving.
The method of setting up a static 404 error page is not complicated, but it is easy to make mistakes.
First, if it is an IIS server, right-click the website you want to manage in IIS Manager, open "Properties"-"Custom Error Message"-select "404"-edit the custom error attributes.
It is important to note that in the "Message Type", you must select "File" or "Default" instead of "URL", otherwise the "200" status code will be returned.
Secondly, if it is an Apache server, if you want to create a 404 page, add the code to the.htaccess file: ErrorDocument 404/Error.html (note that the main domain name should not be preceded by/Error.html here, otherwise the status code returned will be 302 or 200 status code), then write an html as the 404 page, name it Error.html, and place this Error.html file in the root directory of the website.
Finally, after setting the 404 error page, be sure to check the status code, enter a web page that does not exist, and use the http status check tool to check its return value. If the return value is 404, it is correct, and if it is 200, it is incorrect. Be careful not to direct the 404 error directly to the home page of the website, which will cause the home page to not be included; the correct way should be to make an error 404 page, and there is a link on the error page that points to the home page.
Among Google Webmaster Tools is an "enhanced 404 page" tool that you may wish to use.
404 error pages are easy to make. Now some space providers provide 404 error page definitions. Just upload an html file after generation. I have used Wanwang and Western Digital spaces, both of which support them and it is easy to make 404 pages. My forum created 404 error pages, and I also created this blog. If you don't believe me, you can try it
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