In our SP2013 farm, we are using continuous crawling. The content source is setup to crawl entire web application. No rule is set.
In one of new added site collection, there is a default "Pages" library which store all the aspx web pages. Under "Pages" library there are several subfolders. Under the subfolders there are several aspx web pages, too.
All the aspx pages under "Pages" are crawled as expected. However, by some reason, even after full crawl, all the aspx pages under "Pages/subfolderXXX" are not being crawled. I checked against other site collections on this farm have do not have problem.
What can be went wrong?