I was having issues building certain parts of the Signals library in Visual Studio 2008 b2. It was mentioned elsewhere, but I didn't see a proposed fix. Here are the patches against trunk to get it building again. Index: named_slot_map.hpp =================================================================== --- named_slot_map.hpp (revision 41161) +++ named_slot_map.hpp (working copy) @@ -127,7 +127,7 @@ || slot_ == other.slot_)); } -#if BOOST_WORKAROUND(_MSC_VER, <= 1400) +#if BOOST_WORKAROUND(_MSC_VER, <= 1500) void decrement(); void advance(difference_type); #endif Index: named_slot_map.cpp =================================================================== --- named_slot_map.cpp (revision 41161) +++ named_slot_map.cpp (working copy) @@ -24,7 +24,7 @@ typedef slot_container_type::const_iterator const_group_iterator; -#if BOOST_WORKAROUND(_MSC_VER, <= 1400) +#if BOOST_WORKAROUND(_MSC_VER, <= 1500) void named_slot_map_iterator::decrement() { assert(false); } void named_slot_map_iterator::advance(difference_type) { assert(false); } #endif As you can see, the changes are simple and just bring the workaround check up to the newest build version. I realize that this isn't the final release I'm running against, but given the history here, I would be very surprised if this wasn't necessary in the final build. Jared