dvd/cd-rom drive missing, vostro 200

This is the drive that used to show up earlier as my dvd/cd-rom drive: HL-DT-ST DVD+-RW GSA-H31N ATA Device I am using a vostro 200 desktop. Now the d drive is missing when I open up my computer or even when I check in the Device Manager. Please help.....

If this is not the right forum please guide me to the right forum... Am very new to the dell support forum...