Some blog owners think that private blogs can't be indexed, by the search engine robots. Given the way private blogs work, search engine access is not directly restricted - even though indexing activity is impeded.
People are prevented from viewing a private blog, only because Blogger displays the private blog interstitial in front of the blog display.
This blog is open to invited readers onlyOther than the presence of that display, access to the blog is not affected. This detail becomes important, for some potential readers who are accessing the Internet through some Local Area Networks.
It doesn't look like you have been invited to read this blog. If you think this is a mistake, you might want to contact the blog author and request an invitation.
Search engines are not directly affected by the private blog status - though there are interesting details.
- The blog description, when indexed, will contain the text of the interstitial notice.
- Private blogs do not publish newsfeeds - and with newsfeeds used to facilitate indexing, the indexing process is not as consistent as with public blogs.
- The dashboard Privacy setting, which generates an entry in the "robots.txt" file, is advisory only, to search engine robots.
The interstitial notice is authoritative to people, when viewing the blog.
The notice does not block robots. Robots are stopped only when they voluntarily accept the relevant settings in "robots.txt".
The text content of the interstitial advice will replace the blog description, in SERP displays.
This blog is open to invited readers onlyWithout an actual blog description, potential blog readers won't feel very encouraged to view the blog. Even when clicking on the SERP entry, the would be blog reader is still taken to the interstitial, and goes no farther.
This blog is open to invited readers only
Private blogs do not publish newsfeeds. Since the newsfeed provides the Blogger equivalent of the sitemap, a typical private Blogger blog has no sitemap - and search engine indexing activity is not as regular.
The settings in the "robots.txt" file, which specifies bots and access, is not authoritative. Acceptance of the "robots.txt" settings is left to the discretion of each different robot - and a robot which does not observe the settings can access any website.
A private blog can be indexed - though without free access by readers to a private blog, there will be less links referencing the blog - and less indirect search engine activity.
Less links referencing the blog leads to less indexing, by the search engines. Less indexing leads to less entries in SERPs, poorer SERP positioning - and relative lack of success when using search engine cache, to search the blog.
With a private blog, you'll be much more successful using a direct blog search.