I'm getting really sick of trying to keep NPCs alive in some of these missions, so I'm curious if there's a console command to set them as essential. And before anyone tells me to use the search bar, I tried.
In certain quests, resurrecting the NPC might not do you any good. If the NPC is one that you need to keep alive, you may get a journal entry whenever they die telling you "So-and-so has died. The quest has failed," or whatever. I don't think you can use the console to fix this, either, because if I remember correctly, even though you can use the console to jump to various stages of a quest, you can't jump backwards through those stages.
Of course, if the quest doesn't end upon the NPC's death, then you can just use the console to resurrect them. Alternately, you could use the console to ramp up the NPC's stats (like set their health to 1000 or something).
< System Message > -- GODZIRRA IS ATTACK JAPAN! LUN FO YOU RIFES! ~ Divinehero (on why the FFXI servers are down)