my D DRIVE AS GONE ?

hi im trying to play films on my toshiba laptop and it wont play n im trying to install my webcam but i cant as my cd drive not working i put the cd in and they just dont load up i clicked on my computer and my D drive as gone all iv got there is my C drive and E drive. what do i do to get me D drive back its happend to me before but i phone pc world up and they went through it with i had to go through loads little setting things but iv forgot how to and i cant phone them coz my garantee as ran out. please help me thanks