Some Vista and Windows 7 users must disable/uninstall the 'Infrared' device (varies from machine to machine, but has that same line in the name) to access the tilde key.
In this case, type several tabs to move the cursor in before entering your commands. The HUD will disappear and you will get a prompt ( |) in the lower left corner of the screen where codes can be input. (Example: §, ½ or | on Scandinavian (Swedish, Danish, Norwegian etc), caret ( ^) on German keyboards, ² on French ones, \ or | on Italian Keyboards, ' on Brazilian Keyboards, ' on Turkish keyboards). The key is the top left key under escape, on non-US keyboards.
Other keyboard layouts will differ, but the key is usually to the left of 1, and just under the Escape key ( Esc). The grave accent key shifts to tilde ( ~) on US keyboards, and the not symbol ( ¬) on UK keyboards. To access the console, use the grave accent key ( `) while in-game (Unpaused).
