Hello, I am using the current boost (1.35) from the SVN, built with Visual Studio 2008 in 32 bit mode. The debug build of my project works fine, but unfortunately there is a linker error when building my application with the release configuration. 1>LINK : fatal error LNK1104: cannot open file 'libboost_iostreams-vc90-mt-s-1_35.lib' The boost library path is correct - and there is definitely no 'libboost_iostreams-vc90-mt-s-1_35.lib'. I build use using bjam: bjam --toolset=msvc-9.0 -j4 -sZLIB_INCLUDE=..\..\..\..\zlib-1.2.3 -sZLIB_SOURCE=..\..\..\..\zlib-1.2.3 link=static,shared debug release install bjam --toolset=msvc-9.0 -j4 -sZLIB_INCLUDE=..\..\..\..\zlib-1.2.3 -sZLIB_SOURCE=..\..\..\..\zlib-1.2.3 link=static,shared debug release clean What's wrong? Thank you -Daniel