What is the best approach to handling 404 errors?

[ShootTokyo]

Hello All - I'm a new here and working on the SEO on my site www.shoottokyo.com.   When I am finding 4xx (Client Errors) what is the best way to deal with them?   I am finding an error like this for example:  http://shoottokyo.com/2010/11/28/technology-and-karma/ ‎   This may have been caused when I updated my permalinks from shoottokyo.com/2011/09/postname to shoottokyo.com/postname.  I was using the plug in Permalinks moved permanently to fix them.

Sometimes I am able to find http://shoottokyo.com/a-very-long-week/www.newscafe.jp and I can tell that I simply have a bad link to News Cafe and I can go to the post and correct it but in the case of the first one I can't find out where the crawler even found the problem.  I'm using Wordpress.  Is it best to just use a plugin like 'Redirection' to move the rest that have errors where I cannot find the source of the issue?

Thanks

Dave

[Chris.Menke]

Dave, you can use a tool like  ScreamingFrog or Xenu's Lunk Sleuth to find links pointing to the 404 pages. You can leave the pages to 404 unless you can see in your stats that search was sending you traffic to those pages or you have external links going to them--in that case you'll want to 301 them.

[ShootTokyo]

Thanks for the fast response Chris.   Is the best approach to 301 them using a PlugIn like Redirection?  Is there a better approach or is there downsides to using a plug in to handle this?

[Chris.Menke]

I haven't used that one but I just read up on it.  It looks good.

[Saijo.George]

Hi Dave

404 errors will happen on website and you dont have to usually worry about them ( unless they are in alarmingly high numbers ) . You only want to worry about 301ing 404 pages when you are losing link juice with those.

I would use these 3 methods to find 404s on the site

1. Like Chris mentioned using Screaming Frog

2. Use your Analytics Package and search for traffic landing on the 404 page

3. Use Google Bing Webmaster Tools and see the 404 message warning ( in Crawl Stats area )

Form here you would want to 301 all valid 404 error pages to the close resembling pages ( that visitors will find useful ).