The web site hosting server will typically generate "404 - Not Found" web page, when users attempts to follow a broken or dead link, hence the 404 error is one of the most recognizable errors users can find on the web.
A 404 error should not be confused with "server not found" or similar errors, in which a connection to the destination server could not be made at all. A 404 error indicates that the requested resource may be available again in the future; however, the fact does not guarantee the same content.
How to Handling 404 Error Page On Blogger?
1. Login to your dashboard
2. Go to "Settings" >> "Sites preferences"
3. in the "Error and direction" >> "Custom page not found" click "Edit"
4. Typing your 404 error message
5. Here my custom 404 error code (look like dynamic page):
<img src="http://3.bp.blogspot.com/-LIZY7NPMT-k/T4iFJQYUxBI/AAAAAAAAAAY/fHtfpshsKoI/s1600/404-custom.png" />
<h3>The page you requested was not found</h3>
<p>Sorry, we can not find the page you are looking for. May have been removed, the name changed, or is temporarily unavailable.<br/>
Please check the Website address is spelled correctly.</p>
<b>Another thing to help you:</b><br/>
<li>Navigation To <b><a href="/">Home Page</a></b>, and using a menu or a link to navigate to a specific post.</li>
<li>Navigation To <b><a href="http://www.bloggerbelog.com/p/sitemap.html">Sitemap</a></b>, and choose your article.</li>
6. Save changes and try to access unavailable page, ex: http://www.yourdomain.com/buduh.html