One of my most popular posts is How to block and hide Facebook applications and requests. The post is really old and is probably no longer useful, but I do get a lot of requests from people who want to know how to unblock a Facebook application (e.g. Farmville, Cafe World) once it has been blocked. Here’s how you do it — at least, until Facebook makes another privacy interface change.

First, log into Facebook and go to Account->Privacy Settings.

Look at the bottom of the page for Block Lists and click on Edit your lists.

In the Block Lists, you can manage all of the people and applications you have blocked. I always block people I never I want to have anything to do with (in Block users), but I also block application invites from friends who are app happy (who invite you to every stupid quiz app and game in Facebook land). If I get more than one app invite from someone, I block them.

If you want to re-enable an app you have previously blocked, you’ll find the app in the Blocked applications area. Click on Unblock next to the app in question, and you’re all set. Just don’t invite me to be a user. :)