Well if your keyboard is like mine, you have to press "F Lock" first to use the "pause/break" button or else it is configured as "scrlk".
Then you have to remember to press "F Lock" again once you have unpaused so you can use the function keys.
Also make sure your keyboard configuration has been loaded in the settings.
Wow that must be the most frustrating problem in the world, i would tear my hair out.