I am currently tracking 404 page URL that triggers the "page not found" page. I also checked the "Pages Not Found" report to see the list of all the URL's. Now when I drill down each URL to see its referrer, I find a huge number being shown as "No Referrer". Any idea why?
Also is there any way I can track the internal pages from where the 404 page URL has been originated? For example:
abc.com has a link xyz.com, which on clicked gives a 404 page.
Is it possible to capture abc.com separately so that on drilling down xyz.com, I can see the source (abc.com). !
It is very possible that redirects could be at play. The redirects could either be from the 404 page itself, or a redirect taking them to a bad URL.
To troubleshoot this, you could create a segment where "visits contain page not found", then take a look at just a regular pages report. While those pages aren't 404's, they might provide an indicator to contributors to 404 pages.
I'd also explore properly passing the referrer through redirects. See Redirects and Aliases for details.
Redirects like Gigazelle mentioned are a component. I also find users` bookmarks are a large source of undefined when looking at 404 sources.
For looking at internal 404 sources I use a 3rd party tool. There are several. If you have an internal search engine it should be able to pull that data for you as well.
The other option though less frinedly is your web server logs...
They give you original GET request that led to 404.(both external and internal pages). Will require alot of text parsing...