Google View in 404 Pages

When there is 404 Error, the HTTP response code clearly tells both browsers and search engines that the page doesn’t exist. The content of the page is entirely unrelated to the HTTP response returned by the server. Firstly, a page like this (called a "soft" 404) tells search engines that there’s a real page at that URL. As a result, that URL may be crawled and its content indexed. Because of the time Googlebot spends on non-existent pages, your unique URLs may not be discovered as quickly or visited as frequently and your site’s crawl coverage may be impacted (also, you probably don’t want your site to rank well for the search query [File not found]).

If your page returns 404 Error you can use the following methods

1] You can improve the user experience by configuring your site to display a custom 404 page when returning a 404 response code.

2] you could create a page containing a list of your most popular pages, or a link to your home page, or a feedback link

3] You can also use the Webmaster Tools Custom 404 widget to add a search box and more site search options to your site.

4] You should properly redirect to related pages so that the rank given for the page may not fall

5] Use the 404 Customized page given by Google https://support.google.com/webmasters/bin/answer.py?hl=en&answer=136085 this will automatically search that 404 Page or page related to that 404 page

Referral Websites
https://support.google.com/webmasters/bin/answer.py?l=en&answer=2409443&topic=2446029&ctx=topic
https://support.google.com/webmasters/bin/answer.py?hl=en&answer=136085