If the context-sensitive help file does not appear when you press the F1 key, the problem may be related to the F LOCK key being disabled on your keyboard. The F LOCK key is present on some newer Microsoft and Logitech keyboards. The F LOCK key, depending on its state, will allow the function keys to have more than one operation.
If context-sensitive help does not work for you, do the following:
Verify that you have an F LOCK key on your keyboard.
If you do, check if your F LOCK key is disabled (green indicator light will be turned off). When the F LOCK key is disabled, it disables the primary functionality of the F1 through F12 keys and activates the secondary functionality (e.g. F7 may be mapped to reply in an email message).
Turn on the F LOCK key (green indicator light will be on), and press F1 to check that the context-sensitive help is working properly.