Help please. My dvd rom is disappearing from my computer. It sometimes appears, and sometimes goes away. When it disappears, i cannot find it in the device manager nor it appears in the bios. I tried the registry upper and lower filters but it didn't work. The device works properly, as it opens normally and the cd rotates normally but doesn't appear on the pc. Disattaching the rom from the pc then putting it back solved the issue for a couple of hours only. What should i do?