Hi Benny, I got this message from Thomas: <snip> Hi, I found a bug in the file "os_core_win32.c" The function pj_generate_unique_string() is called before initiializing mutex but needs access to it. You should change it this way: -------------------------------------------------------------------------------- /* Initialize critical section. */ if ((rc=init_mutex(&critical_section_mutex, "pj%p")) != PJ_SUCCESS) return rc; /* Init random seed. */ /* Or probably not. Let application in charge of this */ /* pj_srand( GetCurrentProcessId() ); */ /* Startup GUID. */ guid.ptr = dummy_guid; pj_generate_unique_string( &guid ); </snip> Nearly the latest SVN version. Regards