Precompiled header is used to boost build time since an OGRE project will take quite long time when it is compiled. A complete tutorial to build precompiled header can be found here. But additional configurations will be needed when Visual Studio 2010 is used.
Right click project -> Properties -> Configuration -> All Configuration, C/C++ -> Precompiled Headers, the configurations will be like this :
Try to build the project and errors will appear:
Right click project (again) -> Configuration -> Active (Debug), C/C++ -> Command Line, add “-Zm134” to Additional Options.