Just follow the guide provided by Topanga. Since you are editing blog settings, the settings will only rule that particular blog.

Hope this clarifies 8|

The settings described in the document I linked to involve changes to PHP files which affect ALL blogs. The changes described there are NOT done via the blog settings from the Admin page.

That's why I wrote you should follow Topanga's guide.
I did something similar to ¥åßßå, by putting his code:

$login_required = true;

in a stub file for a blog. That way only the blog is protected and not the complete setup.
This worked fabulously, however I can not guarantee there is no hidden back door to the blog bypassing the login.
These are the steps:
- create a stub file (usually a renamed copy of the file/blog/a_stub.php
- setup the blog so it is called through the stub file (Dashboard -> Blog settings -> URL)
- put the code above into the stub file, right after the opening <?php

Now only people who can login can access the protected blog.

The solution Topanga provides works different. Here the blog is not protected and visible to the world, but the posts in that blog are. They are only seen by members of that blog and you decide who those members are.

Good luck

What you describe is precisely what I want.

Where is Topanga's guide? Can you post the link?

THanks!

It's the same link you gave.

OK, but there is nothing in Topanga's post about using stubs. I'll take a look at the user documentation. Thanks for the suggestion!

There are two different strategies. First there is Topamga's and second there is ¥åßßå's. My solution is an adaptation of ¥åßßå's ideas.
You can use both solutions together, but I think you want to make a choice between them. Simply try and decide what fits your needs.

Good luck

What you 'should' do is make sure that in the targetted blogs, nobody can publish 'public', only protected.
You leave the default_post_status to public, but since there is no public way in those blogs, the posts will apear as protected.

so people can view the protected blog, but not the posts that are per default published as protected.

If you also don't want people to view the empty blog, you must also add the login = required option by Yabba