I'm having trouble building Boost 1.87 on Windows using the latest VS2022. I'm starting from the "x64 Native Tools Command Prompt for VS 2022". I've downloaded the latest ICU binaries and updated my PATH, LIB, and INCLUDE environment variables: set PATH=%PATH%;D:\icu\bin64 set LIB=%LIB%;D:\icu\lib64 set INCLUDE=%INCLUDE%;D:\icu\include I go into my boost directory and run bootstrap.bat. It seems to complete, creating b2.exe. I then run "b2 address-model=64" and it's not finding icu: E:\boost_1_87_0>b2 address-model=64 Performing configuration checks - default address-model : 64-bit [1] - default architecture : x86 [1] Building the Boost C++ Libraries. warning: Graph library does not contain MPI-based parallel components. note: to enable them, add "using mpi ;" to your user-config.jam. note: to suppress this message, pass "--without-graph_parallel" to bjam. - icu : no [2] - iconv (libc) : no [2] - iconv (separate) : no [2] - cxx11_auto_declarations : yes [2] - cxx11_decltype : yes [2] I ctrl-c to quit at this point and looked at my config.log and it doesn't seem to find icu when building has_icu_test.obj: compile-c-c++ bin.v2\libs\locale\build\msvc-14.3\debug\x86_64\link-static\threading-multi\has_icu_test.obj has_icu_test.cpp E:\boost_1_87_0\libs\locale\build\has_icu_test.cpp(6): fatal error C1083: Cannot open include file: 'unicode/coll.h': No such file or directory The file D:\icu\include\unicode\coll.h does exist though. Is there some reason my environment variables don't make it to the processes kicked off by b2? Or am I overlooking something obvious? Any help is greatly appreciated. Cory