Problem adding items to npc with excel

Hi!

I'm currently adding items to the npc's, and as you know excel is the best program to this with, yes i'm adding the things manually. So here's my problem whenever i edited a item in the column Z from "=" to a "1" and saves with excel the world server crashes, but if i do the same save in Notepad++ it works 100%fine. So i wanna know how to be able to use excel without the world server crashing? since notepad doesn't have column takes to long time to try finding the "Z column" So does anyone have experience with excel and how to fix this? :thumbup:

Regards Laitila