How to Unblock Websites on a Mac
If you are a parent of a child who has access to the Internet with a Mac, you might have blocked her from visiting specific websites that you determined are inappropriate for her to view without adult supervision, but then later you decide that you want to unblock access to these sites. You use Apple's Parental Controls to set what websites to block. The setting is locked with your password, which you must enter again later when you want to unblock websites.
Log into your Mac with the administrator password.
Click the "Apple" logo from the Finder menu, and then click "System Preferences."
Click "Parental Controls." Click the icon of the lock, and then type your password at the prompt.
Click the name of the user account that you want to unblock websites for, in the left pane of the Parental Controls window.
Click the "Content" tab."
Click "Customize." A list of blocked websites appears in the "Never Allow These Websites" pane.
Click a website that you want to unblock, to select it.
Click the "Minus" sign to remove the website from the pane. Continue this procedure for each website you want to unblock, and then click "OK."
Click "System Preferences" from the System Preferences menu, and then click "Quick System Preferences."