On my Sith Juggernaut Tank, I was doing the mission "Catalyzing the Conversion" on Belsavis. There are 4 different NPC types that are supposed to drop "Reprogramming-resistant Processors", but they are not showing up among the loot, preventing me from getting the bonus mission "Stage 1 - Converting the Unconvertable". That mission has a Stage 2 and Final Stage before it becomes a separate mission called "Converting the Unconvertable".