Blogspot – Picture Size Limit for Free Storage

Google has never shared the formula for how they choose the thumbnail with us.

However various experiments make me believe that it's the first image over a certain size (perhaps 20k?) which is hosted in Picasa-web-albums/Google+Photos.

I haven't heard or noticed restrictions based on file name - but that's not to say they don't exist.

I documented what I found when investigating this here: http://blogger-hints-and-tips.blogspot.co.uk/2011/07/postsnippet-and-postthumbnail-tools-for.html - but that was in 2011, and there are no guarantees that things have not changed since. I've seen a claim somewhere (but not verified it) that the need for the photo to be Google-hosted was relaxed at some point.

You - or the person concerned - needs to remember enough details to convince Google that they really did create the blog.

There are links to the forgotten password process (that won't work without access to the email), and to the account recovery exam, here:
http://blogger-hints-and-tips.blogspot.com/2010/11/deleting-blogs-and-blog-posts.html

You / they are welcome to take the account recovery exam as many times as you / they wish: some people report success after the 3rd or 4th attempt.

Remember, the flip-side of this question involves people pretending they made blogs that they didn't really make, and asking to have them taken down just because they don't like what is said.

And if they cannot manage to take the blog down, the other option is to load other stuff on to the internet which will put the undesirable content further down the search-engine result pages.