Fix the link, make sure the source you're linking to actually exist where you're linking, etc. A 404 error means the resource can't be found, which means the file or domain or whatever you're linking to doesn't exist.
Restore deleted pages. Sometimes, you delete pages from your website and people still come to your website to find those page you deleted. If somebody tries to find a deleted page, they'll get a 404 error. To fix this, you can usually restore the deleted page.
Did you loses a page/ file that was supposed to be there or are you wanting to redirect a 404 to a custom or home page?
You can fix the error by using methods mentioned below: Redirect the 404 error somewhere else. Correct the source link. Restore deleted pages.
To a visitor instead of a white page that says "Not Found" saw an HTML page with recommended navigational options you need in the file .htaccess add the line: ErrorDocument 404 site.com/404.html
If you're seeing a 404 error it's most likely because you've either linked to the wrong web address or you've deleted that page altogether. What is your site, and the page you're trying to get to etc?
Redirect your 404 webpage to relevant webpage or it is advisable to redirect it to homepage of the website.
You can try many things for solving 404 error. First try to restore deleted pages as they creates the 404 error and you can use your google webmaster tool to find the error pages.
If you are browse wrong url then 404 page will appear or the page you looking for is exist now but link is there. web developer should fix those links if the don't have content.
404 error means page not found, it is not in searches and content not found here. IN SE there is nothing about that page. To, fix 404 error, you have to redirect URL to the working URL, then correct the source link & restore deleted pages. Imp: If you have broken links pointing to 404, will lead to loose page ranking.