I have downloaded boost and did build the boost libraries according to http://www.boost.org/doc/libs/1_55_0/more/getting_started/windows.html and configured VS2008 as well. but when i'm trying to use #include <boost/thread.hpp> it gives following set of compilation errors. 1>C:\Program Files\boost_1_55_0\boost/smart_ptr/detail/sp_counted_base_w32.hpp(74) : error C3861: '_InterlockedIncrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/smart_ptr/detail/sp_counted_base_w32.hpp(93) : error C3861: '_InterlockedCompareExchange': identifier not found 1>C:\Program Files\boost_1_55_0\boost/smart_ptr/detail/sp_counted_base_w32.hpp(101) : error C3861: '_InterlockedDecrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/smart_ptr/detail/sp_counted_base_w32.hpp(110) : error C3861: '_InterlockedIncrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/smart_ptr/detail/sp_counted_base_w32.hpp(115) : error C3861: '_InterlockedDecrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/smart_ptr/detail/spinlock_w32.hpp(62) : error C3861: '_InterlockedExchange': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/thread_data.hpp(130) : error C3861: '_InterlockedIncrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/thread_data.hpp(135) : error C3861: '_InterlockedDecrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/basic_timed_mutex.hpp(52) : error C3861: '_InterlockedExchange': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/basic_timed_mutex.hpp(100) : error C3861: '_InterlockedCompareExchange': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/basic_timed_mutex.hpp(118) : error C3861: '_InterlockedCompareExchange': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/basic_timed_mutex.hpp(147) : error C3861: '_InterlockedDecrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/basic_timed_mutex.hpp(210) : error C3861: '_InterlockedDecrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/basic_timed_mutex.hpp(225) : error C3861: '_InterlockedExchangeAdd': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/basic_timed_mutex.hpp(248) : error C3861: '_InterlockedCompareExchange': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/condition_variable.hpp(68) : error C3861: '_InterlockedIncrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/condition_variable.hpp(73) : error C3861: '_InterlockedDecrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/condition_variable.hpp(110) : error C3861: '_InterlockedIncrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/condition_variable.hpp(115) : error C3861: '_InterlockedDecrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/once.hpp(183) : error C3861: '_InterlockedCompareExchange': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/once.hpp(202) : error C3861: '_InterlockedIncrement': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/once.hpp(205) : error C3861: '_InterlockedExchange': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/once.hpp(218) : error C3861: '_InterlockedExchange': identifier not found 1>C:\Program Files\boost_1_55_0\boost/thread/win32/once.hpp(741) : error C3861: '_InterlockedIncrement': identifier not found help me on this issue. -- Pubudu Bandara Undergraduate Department of Computer Science and Engineering University of Moratuwa