Hi to all.. sorry for the newbie question. I believe I have built the Boost libs correctly. I used: bjam -s"TOOLS=vc7.1" -s"VC71_ROOT=C:\Program Files\Microsoft Visual Studio .NET 2003\Vc7" install The Includes and Libs are in C:\Boost as described in the "Getting Started Guide" Also I didn't get any errors during the building process (that's why I assume the build was succesfull), so I decided to test the libraries and just took one of the examples form the site. Compiled it and got the: "fatal error C1083: Cannot open include file: 'boost/filesystem/operations.hpp': No such file or directory" #include "boost/filesystem/operations.hpp" #include "boost/filesystem/path.hpp" #include <iostream> namespace fs = boost::filesystem; int main( int argc, char* argv[] ) { //removed for brevity... } I also added the path to the environmental variables in windows, under INCLUDE and LIB, but this didn't seem to change anything. Can anyone help me understand why the compiler doesn't find the headers? What am I missing? Thank you in advance for your help... Chris PS. I am really sorry for the newbie question....