 <p>Did you read dlib's <a href="http://dlib.net/compile.html" rel="nofollow">How to compile</a> page? It sounds like you forgot to add dlib/all/source.cpp to your project. Adding that should make those linker errors go away. Also, since you are using Code::Blocks, you will need to tell it to link with these windows libraries: gdi32, comctl32, user32, ws2_32, and imm32. </p> <p>It's also worth pointing out that there is a free version of <a href="http://www.microsoft.com/visualstudio/en-us/products/2010-editions/visual-cpp-express" rel="nofollow">Visual Studio 2010</a> which you can use to compile these C++ programs. If you are compiling on windows I would definitely recommend using this compiler instead of Code::Blocks. </p> <p>On my system (Windows XP in a virtual box VM with 3.5GB of RAM) Code::Blocks compiles without issue using the above method. However, if it refuses to compile dlib/all/source.cpp you should just add the files listed in dlib/all/source.cpp to your project individually instead. The only reason source.cpp is included is for convenience and it really isn't needed. </p>