

Guys as the title states, i am having trouble with my dad's laptop.
Its an old acer 2420 and i took out its hard disk to reformat and reinstall windows.
After i formatted it, a weird problem popped up.
The problem is that whenever i reinsert the hard disk into the laptop, the dvd drive wont work. It has the same problem with my desktop. So, now i cannot install windows through startup on the laptop or my desktop.
*note* The hard disk is a hitachi 40gb notebook ide and i used an adapter to connect it to my Desktop.
Please help! and thx in advance