How do I lock a post in a group?

You can only lock a post if you're a Group Owner or Admin.

Here's how to lock a post in a group:

1.  Click on the post title.
2.  Scroll down to the bottom of the post.
3.  There you will see four buttons ("Delete Post & All Replies", "Lock Post", "Move Post" and "Feature Post") and a drop down menu ("Post Status").
4.  Click the "Lock Post" button to lock the post.