Hacks on a saved map?
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So, I was working on something on a friend's temp/alternate server, and saved/dumped the level. When I load the level in single player World of Minecraft, I can't use hacks. Hacks work when I was on the server, and when I make a new single player map in World of Minecraft. What's going on?
Edit:
I load through "load file," and the map has a .dat file extension.