How can I unblock a friend on Facebook?

[Roger]

To unblock a friend on facebook simply open the facebook account. Right side of the account there is a icon (setting icon).
Click on that setting icon - One drop down list will be open - than after Click on account setting.
You will see many options would be available on the left side of the page.
There will be option named "Blocking" click on it.
Now you can view the page of manage blocking.
2nd option in that page "Block Users" there displays the name of the users whom you have been block, side by side there is also an option to unblock after each name.
Click on that "Unblock" option and there will open a box which will ask you for confirmation to unblock that person again.
Click on Confirm and the person is unblock.