Hi, This is my second attempt to get some help on this issue... Can anyone provide a pointer to the steps required to using a boost lib in a managed C++ dll. I am using boost 1.33.1 with vc7.1. Boost libs were built with default options using bjam (bjam "-sTOOLS=vc-7_1" install). I am able to build a dll, but .net app using the dll crashes when it attempts to call code from the boost libs (in my case date). Building either managed or unmanaged static libs & using in a managed c++ app work fine, so I suspect that the problem is due to dll loader issues. I have tried linking with static & dynamically linked libs (CRT & boost), but the result is the same. I have built the dll with the /NO ENTRY switch & added manual calls to initialise the CRT. This removes the vc warnings, but the dll still cause the app to crash. Thanks in advance Kon Tantos