Protecting MPQs

I heard that w3x, and mpqs have exactly the same compression and format but different extensions. Then would it be possible to protect mpqs?

by protect i assume you mean the prosses of protecting a map.

no.

you can still open protected warcraft 3 maps in an MPQ viewer. they may not have a listfile, mind you. the act of protecting a map is really just making it so that the world editor cannot open the map, whereas the game itself can. if the archive where somehow protected in the sense of a password protected ZIP, then the game couldn't open it.

When people say "map protecting" they are actually referring to a process of damaging and/or deleting some of the editor-only files so that WE would produce an error or crash while loading...
As for MPQ protection...there is a rather simple way of doing so by corrupting the MPQ header (first 4 bytes) using a hex editor. The game ignores this, but *some* MPQ editors might cause an error when opening a MPQ with a damaged header. However this usually isn't the case so no, there is no way.

thx.

LAtelly those 4 bytes are used to sign the map after processing, the optimizer does it and places a VxOP there since war3 doesn't read it, I've seen other tools signing it .

The number of mpq viewers and tools able to read a map with those 4 bytes changed is incredibly big, so nevermind it.