A “soft 404” is when a document describing a 404 error is returned by the server with a 200 OK status code in the HTTP headers.
This tells browsers, search engines, etc that it is a regular page (which should be indexed by search engines) and it takes a human reading it to realise that it is actually an error page.
404 is a HTTP response code which means the ‘Not Found’. When Server unable to find a requested resource from the client, it returns a HTTP Response code 404.
Soft 404 is when server redirects to a customised page to stop user from viewing the requested resource. There might be cases like a 404 has happened or it may not happened. The page requested is available,but that page is not working properly, So rather than ,viewing the partly wokring page, user is redirected to a custom page without providing the resource asked for.In Google’s own words: “This is like a giraffe wearing a name tag that says ‘dog’. Just because the name tag says it’s a dog, doesn’t mean it’s actually a dog. Similarly, just because a page says 404, doesn’t mean it’s returning a 404 status code.” By soft 404 means, user will be redirected to a custom page or other location because of any reasons[might be 404 or anything else.].
The 404 or Not Found error message is a HTTP standard response code indicating that the client was able to communicate with a given server, but the server could not find what was requested.
Basically, Soft 404 is a page that looks like a 404 but returns a HTTP status code 200. I mean, the website might show a “Page Not Found”-style page, but search engines such as Google will see the page and think that it’s an actual live page.
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A “soft 404” is when a document describing a 404 error is returned by the server with a
200 OKstatus code in the HTTP headers.This tells browsers, search engines, etc that it is a regular page (which should be indexed by search engines) and it takes a human reading it to realise that it is actually an error page.
404 is a HTTP response code which means the ‘Not Found’. When Server unable to find a requested resource from the client, it returns a HTTP Response code 404.
Soft 404 is when server redirects to a customised page to stop user from viewing the requested resource. There might be cases like a 404 has happened or it may not happened. The page requested is available,but that page is not working properly, So rather than ,viewing the partly wokring page, user is redirected to a custom page without providing the resource asked for.In Google’s own words: “This is like a giraffe wearing a name tag that says ‘dog’. Just because the name tag says it’s a dog, doesn’t mean it’s actually a dog. Similarly, just because a page says 404, doesn’t mean it’s returning a 404 status code.” By soft 404 means, user will be redirected to a custom page or other location because of any reasons[might be 404 or anything else.].
These urls can be checked for reference::
https://www.hallaminternet.com/what-are-soft-404-errors-will-they-affect-rankings/
http://forums.seochat.com/search-engine-optimization-28/diff-between-404-soft-404-error-467526.html
The 404 or Not Found error message is a HTTP standard response code indicating that the client was able to communicate with a given server, but the server could not find what was requested.
Basically, Soft 404 is a page that looks like a 404 but returns a HTTP status code 200. I mean, the website might show a “Page Not Found”-style page, but search engines such as Google will see the page and think that it’s an actual live page.