I've rescued Haer'Dalis from the mage/wizard, and when I help them open the portal to defend them, I defeat the creatures, and when the last creature comes out *shadow creature (sorry I'm not good with names)* I defeat him, and then the group (Haer'Dalis and his friends)turn against me and attack me, so I can't finish the quest to help them. what should I do?

Replay the fight, but remove all items that behave as turning damage back to source or that do area damage.
That goes for Harbinger sword, spells like fireballs, Keldorn's sword, Cloak of Mirroring, etc.

And do not cast Charm or Domination spells! (now when I think of it, maybe the charm from that creature is responsible....)

If nothing of these works, zip your saved game and mail it to me.

hey thanks, I took off party AI and took off any weapons that did extra damage (i.e burn damage) off to the planar prison.