If you have overlaid keys on keyboards make sure NumLock light is off; hopefully, OEM did not reverse that -- light should mean NumLock is on and you want if off. Do you have two sets of vertical scrollbars on the webpage. If you are inside a textbox, the keyboard controls would apply to the textbox and the textbox scrollbar would move. Test with this page, it has no text boxes and no frames: :http://dmcritchie.mvps.org/firefox/firefox-problems.htm#fx4 If you find the page up and page down is changing to back/forward button within the tab history (particularly on some laptops), see *Bug 640587 – Page up/down behavior changes to "page back/forward" *:https://bugzilla.mozilla.org/show_bug.cgi?id=640587 ---- Sounds like you have the following under control and correct: :Are those settings still in effect when you have the problem. F7 will toggle the accessibility.browsewith caret on(true)/off(false). The settings in about:config still allow you to change them with F7, by including the following in user.js they will be reset each time you restart Firefox. // Get SpaceBar, PageUp, PageDown to work properly if F7 hit accidentally :// see http://dmcritchie.mvps.org/firefox/firefox.htm#caret(problems) : user_pref("accessibility.browsewithcaret", false); : user_pref("accessibility.warn_on_browsewithcaret", true); Press F7 if you get the warning message you were okay but will have to press "No", if you don't get the message then you. Do not put a check in the dialog box -- if you you will not get the warning again until you restart. summary: :http://kb.mozillazine.org/Scrolling_with_arrow_keys_no_longer_works