How to Find Out If a Facebook Friend Blocked Youby David Weedmark
There are several reasons why someone may vanish from your list of Facebook friends. Being blocked by that person is certainly one of those reasons, but it isn't the only one. The person may have unfriended you or deleted his Facebook account. Facebook won't notify you if you have been blocked, but using Facebook Search, old messages, mutual friends and the Facebook public directory, you can often gather enough clues to determine whether or not you have been blocked.
If you no longer see a friend in your Friends list, try typing the person's name in the Search field at the top of any Facebook page. If the person hasn't blocked you and still has an active account, his name should appear near the top of the list. You can click the "See More" link at the bottom of the list to keep searching. If you can't find his name, he may have changed his name, deleted his account or he may have blocked you. If you find your friend listed in the search results, you haven't been blocked. If you click his name and see an "Add Friend" button on his Timeline page, you've been unfriended.
Using Old Messages
Being blocked by someone does not delete Facebook messages. If you suspect you have been blocked and you have shared Facebook messages with that person, you should still be able to find those messages in your message history, provided you haven't deleted them yourself. If the person's picture is now a generic silhouette and if you are unable to send a new message to that person, the person has either blocked you or has deleted his Facebook account.
Using the Public Directory
Facebook has a public directory designed for people without a Facebook account. (See Resources for the link.) If you log out of Facebook, you can use this directory without the search results being affected by a block. You can search alphabetically, but it's faster if you just type the person's name. There is no option to limit searches by city so you may have to scroll through a lot of names, especially if the name is a common one. If you're unable to find the person, it could be because he chose not to make his profile available for public search. If you are able to find him, click the name to go to his Timeline and then log in from that page. If the Timeline is no longer visible, you've been blocked.
There are a couple of ways to find out if you've been blocked through using your mutual friends. The most direct way is to ask a mutual friend if he can still see the person on Facebook. If he can and you can't, you have been blocked. If you don't want to ask your friend directly, wait a day or two and go to the mutual friend's Timeline. No one can control what is seen on someone else's Timeline, so If your former friend disappeared on Tuesday and you see him adding comments or liking posts on your mutual friend's Timeline on Wednesday, you have most probably been blocked.
Information in this article applies to Facebook as it worked in April 2013. It may vary slightly or significantly with other versions or products.