non-existent cache page

if the user agent is “googlebot”, this isn’t a visitor from google, but google requesting autoptimized JS/ CSS based on old cached HTML.

3 possible solution;
* ignore this fact
* never empty your cache
* tell google this file has moved permanently cfr. this thread on the support forum

hope this helps,
frank

Thanks. It is no user agent, but ordinary people who like to visit my website and cannot find it.

in that case you probably have pages in a page cache (plugin) that have references to already-removed autoptimized JS/ CSS, clearing your page cache’s cache should help.

frank