Canonical Tag for a 404 page

[usef4u]

Hi

i have a got a 404 page for example : www.example.com/404.aspx

can i use canonical tag on this page

so that when the search engine hits the page www.example.com/123123123 13123

it will say

Will this be right method ?

[ajmihalic4]

The two most important points expressed in this thread of comments are:

1. There is a reason for 404s, don't 301 everything
2. There is no reason to lose the value of someone linking to your page.

If those 2 statements are true then you should create an individual error page, and then everytime you serve a 404 you should include canonical to that error page. That page should have useful content (explanation of page missing and where you could go), probably a search box, and links to the most valuable content on your site. This satisfies both points.

[oznappies]

The meta redirect tag will keep the link juice on the 404 handler page and not pass the page rank on to the home page. Something you may want to consider if you have a lot of 404's.

[usef4u]

Thanks for your reply,

I have already setted up that and in fact i read something over here...

http://googlewebmastercentral.blogspot.com/2008/08/now-that-weve-bid-farewell-to-soft-404s.html

We feel this technique is fine because it reduces confusion by giving users 10 seconds to make a new selection, only offering the homepage after 10 seconds without the user's input.

But my question is sometimes you can't control how other people linked to you and they link back to us with a url that does not exist. And in googlewebmaster control panel we get an error for the saying Duplicate title - 404 Page Not Found.

For that if i use it should be ok or not

[Getz.pro]

If you love writing code, read on

I like setting my 404 pages to evaluate the incoming URL (the one that failed) and trying to redirect the user to the proper page while 301ing the hand off. If you cannot evaluate the page to a good page, then 301 to the home page. If you can only evaluate to a category level (storefront type site), then 301 them to the category level.

It takes some fiddling around with the code and lookups to the database, but you get a much better experience for the user.

[oznappies]

You could but, you would be better creating a search page so 404's go to www.example.com/search.aspx so users can search for the content they were actually looking for in the first place. Ideally all your pages should have the canonical in the head to ensure trailing / or capitalization errors all pass juice to the correct page and do not get reported as duplicates.