In our current D&D 3.5 campaign we have made enemies with powerful drow vampire clerics. They have an annoying habit of resurrecting as their god is one who brings people back from the dead to have their revenge on whoever killed them.
Our usual method of destroying vampires is to kill them, then when they go gaseous and race off to their coffin, follow them to destroy the coffin/s or expose their coffin to direct daylight or prevent them from reaching their coffin in time. We've done this twice now to the vampire clerics and I'd like to know a more permanent solution in case there is a round 3 (especially as they keep bringing a marilith with them).
Our party has extensive resources so any conceivable 3.5 solution could probably be organised by the party (6 16th level characters).
Is there any way to prevent a person/creature from ever being brought back to life/unlife?
As a fallback against them coming back once they're dead you can always try a wish spell to stop them coming back once you've killed them.
However, if it is True Resurrection that is bringing them back, there is a gotcha;
Even true resurrection can’t restore to life a creature who has died of old age.
Now given that these are Drow anyway this is a bit of a long time to take into consideration; but you could get them by:
** Level draining may work as well here, but I don't think it's as surefire a method.
As an additional thought; you could possibly reincarnate them instead, they will be reasonably likely to come back as a somewhat less long-lived race than a Drow and then make them die of old age. They'll still have died of old age then! However you'd have to true resurrect then, kill them, then reincarnate them as reincarnate doesn't work on undead, this might be getting a little complicated ;)