I'm using libcurl and am getting the following sort of linker errors in VC++ 10.
1>main.obj : error LNK2019: unresolved external symbol __imp__curl_easy_strerror referenced in function "class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > __cdecl curl_httpget(class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (?curl_httpget@@YA?AV?$basic_string@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@ABV12@@Z)
__imp__ prefix appears whenever you are linking to a DLL. It does not appear when linking to statically linked libraries. Most likely the code is generated to be linked against a DLL import lib, but you have linked it with a static lib instead.
The prefix is added when you mark the imported function with
__declspec(dllimport) - make sure your imports are not using this when not linking against a DLL.