Question : Problem: CD/DVD drive no being recognised on laptop

I have an Acer laptop where the CD/DVD drive will sometimes be recognises by the BIOS and other times not.  Windows doesn't see the drive at all.

I have tried a replacement CD drive but still get the same results.

Am i looking at a motherboard problem here or have i missed something?

Answer : Problem: CD/DVD drive no being recognised on laptop

Possible the motherboard failed, but as you said, sometime it is still recognized in bios. Let play with registry first, see if it could help. If not, flash the bios ... how old the laptop and what make/model?