This can cause Search Console to report that everything is alright, whereas, in reality, some of your desktop pages may be missing from the index.
John Mueller, a Google Search Relations Advocate, verified this morning that Google has modified how it handles soft 404 detection and classifications. The search engine now analyses each page based on the device it is being viewed on, and it may be possible to assign distinct soft 404 classifications to the same URL on mobile and desktop.
What are soft 404s?
A soft 404 occurs when a page returns an HTTP status code of 200, indicating that everything is fine. However, the page does not really load content or cannot be located, and should most likely produce a 404 error. When this happens, Google will mark those pages as soft 404s, and the URL will be treated as a real 404, with the page not being indexed.
Google stated that it has modified the way it classifies soft 404s and now looks at a URL based on the device type. As a result, if Google detects a URL and hits it on the desktop before seeing it on mobile. It may send a soft 404 for the desktop but not the mobile. In other words, Google detects the soft 404 status on a per-URL basis, as well as by device type. According to the complaints I’ve recorded, this adjustment occurred around a month ago.
Why this can be an issue
There have been a number of instances where SEOs have seen one of two things:
- When using Google Search, Google may not index pages, or
- SEOs may notice an increase in soft 404 errors in Search Console but not in Google Search.
What’s going on
Google will not report soft 404 errors in Search Console if a website returns well for the mobile device type. Because Google only gives soft 404s errors based on mobile crawls. Search Console will not report an error if the page functions correctly on mobile. However, Google may assign soft 404 faults to your desktop version, in which case, you will receive a notification. When you search Google on a desktop, some pages may not be indexed and appear in Google Search. Simultaneously, Search Console reports that everything is good, even though it is only fine on mobile and not on desktop.
“We do show soft 404s in Search Console, but just for the mobile version. So, if everything is fine on your end for the mobile version, Search Console will show that it has been indexed normally. “However, you won’t be able to see that immediately in Search Console for desktop,” Mueller explained.
Google working on a solution
The Google team is attempting to improve its soft 404 categories. And if you have any instances to contribute, post them in the Google support forums or tweet them to @johnmu.
Why we care
This change could be tied to indexing troubles in Google Search that began roughly a month ago or a rise in soft 404s that occurred around that time. Send Google samples of URLs that are experiencing this issue, and Google may be able to resolve the issue in the future. If your site is affected by this change, it may experience traffic difficulties.