why can't i play downloaded quest when i load them it says inval password can some one help i have zc 2.10
why can't i
It sounds like you are opening zquest (the quest editor), which is a program separate from the quest player. The quests are passworded so they cannot be edited. The quest player will be able to load them without the password.
Instructions are in the FAQs.
See: How do I load a custom quest?