This seems like as good a time as any to discuss how to block commenters on your blog. There are essentially three ways to block people.
The first and easiest is to mark all of their comments as spam. You can do this from the Dashboard->Comments screen or directly from the WordPress app on your phone. Unfortunately you can’t do this directly from your public blog, you have to do it through the dashboard. In any case, after a few tries, the spam filter learns that a particular commenter always gets flagged as spam and automatically puts those messages in the spam box.
The next way to block people is by moderating the comments. You can either set all comments to require moderation or you can set filters for specific phrases that will set a comment for moderation. Both of these settings are found in the dashboard under Settings->Discussion. The global moderation setting is found in the “Before a comment appears” section. It’s the option labeled “Comment must be manually approved.” Unchecking this box means every comment has to be approved before it shows up on the public site. The user or word-specific setting is the big text box in the “Comment moderation” section. If any part of a comment – body, ip address, email address, or username – matches the word(s) you put in this box, it will be held for moderation.
The last way to block people is by sending the comments to Trash. This filter is is set in the “Comment blacklist” section of the Discussion page. This works the same way as the comment moderation filter mentioned above – it filters on all available message fields.
You have to be careful with the filters because you can end up filtering stuff you don’t want to. For instance, if you want to block a user called “Latrodectus” then you would put that word in the blacklist filter text box. However, if some other user comments saying “Latrodectus is such a troll” then that comment would also go to trash. Incidentally, this may be a reason why some of your comments don’t show up on other people’s blogs. It’s up to the blogger to check their spam, pending moderation, and trash bins for errant messages.
So depending on what level of involvement you want to have in blocking users, you have several options. Each has their pluses and minuses and you can’t completely stay hands off, but it can make your life a little easier, especially when you have a user who consistently trolls every post you make. I hope this little walk-through helped everyone. If you have questions, post them in the comments. Just don’t use the work Latrodectus or else they’ll go to my trash can 🙂