|Could just be a website error. You don't say which browser you are using.|
If you are using IE, go to Tools > Internet Options > Advanced.
Under the heading "Browsing" and check any entries that refer to Disabling script debugging. Apply & OK your way out.
Close IE then go back and try Facebook again.
If you have some other browser onboard see if that does the same.
Always pop back and let us know the outcome - thanks