Linker Problems with OpenSSL in Visual Studio 2013

Question

I am using one OpenSSL function in my simple program. But I am getting unresolved symbols for that one function. Below is my project properties setup - I've followed other posts that describe how to include OpenSSL in a project and performed those instructions. Whats wrong with my Visual Studio 2013 setup?

Error 1 error LNK2019: unresolved external symbol _SHA1 referenced in function _main

Could it be that I am using the 64 bit OpenSSL version? Is it that my project is <CharacterSet>Unicode</CharacterSet>?

... Code generation = Multi-threaded Debug DLL (/MDd)

<ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
    <ClCompile>
      <WarningLevel>Level3</WarningLevel>
      <Optimization>Disabled</Optimization>
      <SDLCheck>true</SDLCheck>
      <AdditionalIncludeDirectories>C:\OpenSSL-Win64\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
    </ClCompile>
    <Link>
      <GenerateDebugInformation>true</GenerateDebugInformation>
      <AdditionalLibraryDirectories>C:\OpenSSL-Win64\lib;C:\OpenSSL-Win64\lib\VC\static;%(AdditionalLibraryDirectories)</AdditionalLibraryDirectories>
      <AdditionalDependencies>libeay32.lib;libeay32MDd.lib;ssleay32.lib;ssleay32MDd.lib;%(AdditionalDependencies)</AdditionalDependencies>
    </Link>
</ItemDefinitionGroup>

Solution:

The problem was I was linking to the 64 bit static libraries when I should be linking to the 32 bit static libraries. That fixes it:

So change all >C:\OpenSSL-Win64\... to >C:\OpenSSL-Win32\.... And install the OpenSSL 32 bit installer.

sazr sazr · Accepted Answer · 2016-07-25T06:28:39

The problem was I was linking to the 64 bit static libraries when I should be linking to the 32 bit static libraries. That fixes it:

So change all C:\OpenSSL-Win64\... to C:\OpenSSL-Win32\..... And install the OpenSSL 32 bit installer.

Linker Problems with OpenSSL in Visual Studio 2013

1 Answers