Trigger doesn't exist

ok i have a question. when i try to open certain maps that other people have made(not for stealing purposes mind you, for learning purposes to see how to do things they have done.) i occasionally get an error message that tells me that a trigger does not exist or trigger not found or something along those lines. than after that it closes my warcraft map editor and i have to reboot. why is that happening?

One of two reasons:

1. The map is protected to stop people from stealing ideas, triggers etc.

2. The map was created using an advanced world editor like UMSWE or WEU.

is there ne way u can determine which one it is exactly? and is there a way i can open it ne way?

Simply put, the triggers are not there because the creators don't want people to just rip it from them. If you have a question, perhaps you should try tracking down the creator.

And, no; you can't undo it. That's the whole point of it.

unless u no jass i need 2 learn it..
i gave up trying 2 find innit...

There is no jass function that says Map Initalization (if that's what you mean)