XP doesn't recognize my dvd/cd burner

My Windows XP Home Edition doesn't recognize my dvd/cd burner. In systems folder they're working fine, i.e. in Control Panel, System Folder/Hardware/Device Manager/DVD CD-ROM Drives/Hp DVD Writer 400c [my burner]/Properties/Device Status/"This device is working properly." That's why I said it's probably a registry issue. I've uninstalled and reinstall Nero, PowerISO, and reinstalled all my Drivers, and still can't get my hp dvd writer / cd-writer combo [my burner] to recognize a dvd/cd. I've gone an uninstalled my burner and then rebooted for an automatic reinstallation. No help. I suspect it's a registry issue. Does anyone know what could've shut down my burner and what I can do to get XP Home Edition to recognize it?