[Boost-users] [Property_tree] using find to find a key

Hi: I am declaring a property_tree, pulating this with an ini file. I then need to find out whether a section (key) is present, so I'm doing: boost::property_tree::ptree::assoc_iterator it =IniTree.find(key); if (it !=boost::property_tree::ptree::not_found) using visual c++ 2010 I get an error c2678, telling me that no operand is able to use these two values. Can someone please tell me what I'm doing wrong, as I can normally do this for std::vectors etc! Cheers Sean.