You can use Facebook privacy settings to restrict the visibility of your content and safeguard your privacy. Many users choose to apply the "Friends Only" option when adjusting content privacy settings. This ensures that only Facebook friends can access their content. If you're unable to view someone's Facebook account, it's likely that you're not friends, or that the person has blocked you. If you've been blocked, only the blocker can remove the block to allow you access to his content. If you haven't been blocked, you can send a friend request. If your request is accepted, you'll no longer be blocked from viewing that user's account.
Sign in to your Facebook account using your e-mail address and password.
Type the name of the member whose account you wish to add in the search box at the top of any page. Click the name as it appears in the search results list.
Click the "Add as Friend" button in the upper-right corner of the profile page to send a friend request. When your request is confirmed, you will no longer be blocked from accessing that user's account.
If you've been blocked by a user, you will not see her name in the Facebook search results, and you will not have the ability to send a friend request. The user who initiated the block must remove it and request to add you as a friend.