Mike has a CD player with a tray that's jammed up. Leo says it's likely a titled CD that's blocked it and it's jammed. It may also be a torn table that has unglued itself and is gumming up the works. There may be a tiny hole that he can use a paperclip to free up the mechanism. Outside of that, he'll have to take it apart.
John is having an issue with his optical drive on his computer after a Windows 10 update. Leo says to check the cables to see if there's a bad cable first. Since the EFI Setup/BIOS doesn't see it, then that points to a hardware issue. It could be a bad board. He should try clearing the ESCD data in the memory. That could help. He can look in setup for it. There may also be a jumper on the motherboard to do it. If he still can't see it, then it's likely a bad CD player circuit board. The good news is, CD players are cheap.