I also get 16, because MSDN says:

"The joyGetNumDevs function returns the number of joysticks supported by the current driver or zero if no driver is installed.
...
Use the joyGetPos function to determine whether a given joystick is physically attached to the system. If the specified joystick is not connected, joyGetPos returns a JOYERR_UNPLUGGED error value."

But for me the joyGetPos() always returns BAD_PARAMETERS (=165) and never OK (=0) or UNPLAGGED (=166?).

I can not understand what goes wrong!