Unable to load DLL 'System.Security.Cryptography.Native.OpenSsl' when creating new HttpClient

System.DllNotFoundException: Unable to load DLL 'System.Security.Cryptography.Native.OpenSsl': The specified module could not be found. almost always means "I can't find OpenSSL" (libcrypto.1.0.0.dylib / libssl.1.0.0.dylib).

There are three major workarounds.

1. You have your customer follow the .NET Core for macOS prerequisites from https://www.microsoft.com/net/core#macos:

   $ brew update
   $ brew install openssl
   $ mkdir -p /usr/local/lib
   $ ln -s /usr/local/opt/openssl/lib/libcrypto.1.0.0.dylib /usr/local/lib/
   $ ln -s /usr/local/opt/openssl/lib/libssl.1.0.0.dylib /usr/local/lib/
   

2. If you have done a standalone build you can take the libcrypto.1.0.0.dylib and libssl.1.0.0.dylib and copy them into your application directory.

   • Technically, they need to be in the same directory as System.Security.Cryptography.Native.OpenSsl.dylib.
   • Be careful with this, since you're distributing a security component. Your local copy will trump a system installation copy, so you'll need to republish after any OpenSSL security releases.
3. You wait a little bit for .NET Core 2.0, because OpenSSL is no longer a primary dependency on macOS (https://github.com/dotnet/corefx/issues/9394).

The solution that worked for me was the second proposed by @bartonjs.

I had to modify my libssl.dylib since she referenced libcrypto with an absolute path.

otool -l libssl.1.0.0.dylib 
showed the absolute path

install_name_tool -change usr/../Cellar/.. @rpath/libcrypto.1.0.0.dylib libssl.1.0.0.dylib
to change the path