Zlib.lib(deflate.obj) : error LNK2005: _deflate_copyright already defined in zlibstat.lib(deflate.obj)

1>IlmImf.lib(ImfZipCompressor.obj) : error LNK2019: unresolved external symbol _compress@16 referenced in function "public: virtual int __thiscall Imf::ZipCompressor::compress(char const *,int,int,char const * &)" (?compress@ZipCompressor@Imf@@UAEHPBDHHAAPBD@Z)
1>IlmImf.lib(ImfPxr24Compressor.obj) : error LNK2001: unresolved external symbol _compress@16
1>IlmImf.lib(ImfZipCompressor.obj) : error LNK2019: unresolved external symbol _uncompress@16 referenced in function "public: virtual int __thiscall Imf::ZipCompressor::uncompress(char const *,int,int,char const * &)" (?uncompress@ZipCompressor@Imf@@UAEHPBDHHAAPBD@Z)
1>IlmImf.lib(ImfPxr24Compressor.obj) : error LNK2001: unresolved external symbol _uncompress@16

1>IFXLocalImageTools.lib(cifxlocalimagetools.obj) : error LNK2019: unresolved external symbol _compress2 referenced in function "private: int __thiscall CIFXLocalImageTools::CompressImageZlib(void *,struct STextureSourceInfo *,void * *)" (?CompressImageZlib@CIFXLocalImageTools@@AAEHPAXPAUSTextureSourceInfo@@PAPAX@Z)
1>IFXLocalImageTools.lib(cifxlocalimagetools.obj) : error LNK2019: unresolved external symbol _uncompress referenced in function "private: int __thiscall CIFXLocalImageTools::DecompressImageZlib(void *,struct STextureSourceInfo *,void * *)" (?DecompressImageZlib@CIFXLocalImageTools@@AAEHPAXPAUSTextureSourceInfo@@PAPAX@Z)

Linker Tools Error LNK2005

symbol already defined in object

The given symbol, displayed in its decorated form, was multiply defined.

Tips

One of the following may be a cause:

The most common cause of this error is accidentally linking with both the single-threaded and multithreaded libraries. Ensure that the application project file includes only the appropriate libraries and that any third-party libraries have appropriately created single-threaded or multithreaded versions.


The given symbol was a packaged function (created by compiling with /Gy) and was included in more than one file but was changed between compilations. Recompile all files that include the symbol.


The given symbol was defined differently in two member objects in different libraries, and both member objects were used.


An absolute was defined twice, with a different value in each definition.
This error is followed by fatal error LNK1169.

The problem is that one of the two projects is using Multi-threaded DLL while the other is using Multi-threaded (without DLL in it) in Project Properties -> Configuration Properties -> C/C++ -> Code generation.

Happened to me several times.

Make sure to "synchronize" that setting even for release builds, and for each possible combination (debug, non debug, etc)

In the project properties for ALL projects, check that they all use the same runtime type: either DLL or static

This can be found under Project Properties -> C/C++ -> Code Generation -> Runtime Library. Make sure you have the Release x64 build selected.

The particular value isn't very important (in terms of compile errors) but they should all be the same