Click & destination
Destination not crawlable
What Google's rule says
Google's stated rule is that the declared click-through URL leads to a landing page that could not be crawled. Google names robots.txt failures, DNS errors and server errors as the common causes.
What actually causes it
- A robots.txt that blocks Google's ads crawler, deliberately or by inheritance.
- A landing page behind a sign-in — ad destinations have to be publicly reachable.
- A server that returns 403, 404, 500 or a DNS failure to the crawler while serving humans normally.
- A page slow enough that the crawl request times out before completing.
How to fix it
Fetch the exact declared URL from outside your network and check the status code, then read robots.txt. If the site blocks crawlers by default, the ads crawler has to be allowed by name.
The part that is not obvious
The trap is a robots.txt written for search engines. Google documents that AdsBot ignores the global `User-agent: *` rule — with the ad publisher's permission — so a site-wide disallow that stops every other crawler does not stop this one, and, more painfully, a site-wide allow does not grant it access either. AdsBot has to be addressed by name with `User-agent: AdsBot-Google`. That is why a landing page can rank perfectly well in search and still be disapproved as uncrawlable: the two crawlers are reading different rules in the same file.
Related reasons
Reason name verified against Google special-case crawlers — Google for Developers on 30 July 2026. The causes and fix above are practitioner guidance, not Google policy text.