FAQ Question #121

No. There is no way to ban a specific person from viewing your public journal entries. To restrict who can see an entry, you must alter its security level (http://www.livejournal.com/support/faqbrowse.bml?faqid=24). If you make a public entry, it is visible to people who aren't on your Friends list, and anyone can read it.

Banning someone from reading your journal when they're logged in under a certain username would be pointless; they could still read your public posts by simply logging out. Even if you could also restrict access to logged-in users, the person you want to ban could easily make another account and continue to view your public posts.

If you could ban someone by IP address, you would end up banning other people too, and the person you wanted to ban could still view your journal from a computer that connects to the internet differently.

Since any attempt to block someone from reading public entries could be circumvented, LiveJournal does not offer such an option. If someone can find your journal, the only way to stop them from reading your posts is to make the entries non-public (http://www.livejournal.com/support/faqbrowse.bml?faqid=120).

You can, however, ban an individual user from commenting in your journal (http://www.livejournal.com/support/faqbrowse.bml?faqid=20). If the user creates new accounts to get around that ban, you will be aware of it, and you might be able to take further steps to prevent any abuse (http://www.livejournal.com/support/faqbrowse.bml?faqcat=abuse).