There are several reasons why a server returns a 404 not found error
The server does not find the resource
When a server returns a 404 error, it means that this server was unable to find a resource. This resource can be a picture file like .jpg, .png, an HTML page (like .html), a PDF file or a
Malformed URL:
If there is a spelling error in the URL, the server will be unable to find the resource and return a 404 error page. That’s why it is important to check the pathname to avoid any spelling error.
Server problems with some characters:
Sometimes, due to a bad server setting, server
Wrong path
It is possible that the directories that were mentioned in the path name aren’t the right ones. For
Case-sensitive path
Some servers have the abilities to make path case-sensitive. For example, apache servers may return a 404 error page when receiving the request to get “/myFilename.php” while the resource is “/myfilemame.php”.