Using MSVC 2010 I have set both zlib and assimp to static libs, which use the Multi-threaded DLL (/MD) option, as to avoid any extra DLL dependency issues. They both compile without error or warning. But when I try to link my project against assimp.lib, I get the following output:
[source lang="cpp"]2>assimp.lib(XGLLoader.obj) : error LNK2001: unresolved external symbol _inflateEnd
2>assimp.lib(BlenderLoader.obj) : error LNK2001: unresolved external symbol _inflateEnd
2>assimp.lib(unzip.obj) : error LNK2001: unresolved external symbol _inflateEnd
2>assimp.lib(XFileParser.obj) : error LNK2001: unresolved external symbol _inflateEnd
2>assimp.lib(XGLLoader.obj) : error LNK2001: unresolved external symbol _inflate
2>assimp.lib(BlenderLoader.obj) : error LNK2001: unresolved external symbol _inflate
2>assimp.lib(unzip.obj) : error LNK2001: unresolved external symbol _inflate
2>assimp.lib(XFileParser.obj) : error LNK2001: unresolved external symbol _inflate
2>assimp.lib(XGLLoader.obj) : error LNK2001: unresolved external symbol _inflateInit2_
2>assimp.lib(BlenderLoader.obj) : error LNK2001: unresolved external symbol _inflateInit2_
2>assimp.lib(unzip.obj) : error LNK2001: unresolved external symbol _inflateInit2_
2>assimp.lib(XFileParser.obj) : error LNK2001: unresolved external symbol _inflateInit2_
2>assimp.lib(unzip.obj) : error LNK2001: unresolved external symbol _crc32
2>assimp.lib(unzip.obj) : error LNK2001: unresolved external symbol _get_crc_table
2>assimp.lib(XFileParser.obj) : error LNK2001: unresolved external symbol _inflateSetDictionary
2>assimp.lib(XFileParser.obj) : error LNK2001: unresolved external symbol _inflateReset
2>C:\pathto\myproject.exe : fatal error LNK1120: 7 unresolved externals[/source]
I have tried removing the ZLIB_WINAPI flag from the zlib project, and I still get these errors. I have even tried linking my project to zlib.lib, adding these functions to assimp's "General -> Librarian -> Exported Name Functions" list, and still no dice. Does anyone know how to solve this?

Well, after I added the same preprocessor flags that zlib uses into Assimp's project settings, and changed all "extern" keywords in unzip.h and unzip.c to "ZEXTERN", the errors disappeared.