Crawl errors on redirecting pages regularly appeared in Webmaster Tools and this often confused many webmasters; but glad to say Google decided to get rid of this confusion through offering an easier and simple diagnosis.
Long back webmasters used to report the error on the original redirecting URL but as of now the error will be shown on the final URL – the one that actually returns the error code.
For instance, if URL A redirects to URL B, which then becomes an error, that kind of an error is not of much significance but in the past, Webmasters would report the discovered at the end under the URL A. But as of now, the error will instead be reported as URL B.
Website Error Analyst, John Mueller says, “This makes it much easier to diagnose the crawl errors as they’re shown in Webmaster tools. Using tools like curl or your favorite online server header checker, you can now easily confirm that this error is actually taking place on URL B.”
He added, “This change may also be visible in the total error counts for some websites.”
A good example that supports Mueller’s sentiments is that of a site moving to a new domain, whereby you only see these errors for the new domain (assuming the old domain redirects correctly), which can cause noticeable changes in the total error counts for those sites.
Worth noting is that these changes only affects how these crawl errors are shown in Webmaster Tools. It’s also important for users to bear in mind that having crawl errors for URLs that should be returning errors (e.g. they don’t exist) does not negatively imact the entire website’s indexing or ranking.
This change might serve as a solution in tracking down crawl errors let alone cleaning up the accidental ones that you weren’t aware of.
Any questions regarding this new service should be posted in the Google Webmaster Help forum.