Appharbor Github build error : assemblies doesn't exist

Question

I have a C# .net project running on .net framework 4.5 on GitHub. I have added the mongodb C# driver using nuget package. On the AppHarbor, I have installed MongoHQ addon. However when I deploy my code its giving build errors as below. I tried to uninstall and once again install the package and build, but still it gives me the same error. In the CS proj file I see the path as below with net35, I am not sure why is it so since the target framework is 4.5. I read all the Appharbor docs and it says it supports .net4.5 now. Please let me know if I am missing something.

Build Error:

 Considered "C:\Program Files (x86)\Microsoft\Contracts\PublicAssemblies\v3.5\MongoDB.Bson.dll", but it didn't exist.
                         Considered "C:\Program Files (x86)\Microsoft\Contracts\PublicAssemblies\v3.5\MongoDB.Bson.exe", but it didn't exist.
                         Considered "C:\Program Files (x86)\Microsoft SQL Server\100\SDK\Assemblies\MongoDB.Bson.winmd", but it didn't exist.
                         Considered "C:\Program Files (x86)\Microsoft SQL Server\100\SDK\Assemblies\MongoDB.Bson.dll", but it didn't exist.
                         Considered "C:\Program Files (x86)\Microsoft SQL Server\100\SDK\Assemblies\MongoDB.Bson.exe", but it didn't exist.
                         Considered "C:\Program Files (x86)\Microsoft.NET\ADOMD.NET\100\MongoDB.Bson.winmd", but it didn't exist.
                         Considered "C:\Program Files (x86)\Microsoft.NET\ADOMD.NET\100\MongoDB.Bson.dll", but it didn't exist.
             3>CopyFilesToOutputDirectory:
Considered "C:\Program Files (x86)\Microsoft SQL Server\100\SDK\Assemblies\MongoDB.Bson.exe", but it didn't exist.
                 Considered "C:\Program Files\IIS\Microsoft Web Deploy V3\MongoDB.Bson.winmd", but it didn't exist.
                 Considered "C:\Program Files\IIS\Microsoft Web Deploy V3\MongoDB.Bson.dll", but it didn't exist.
                 Considered "C:\Program Files\IIS\Microsoft Web Deploy V3\MongoDB.Bson.exe", but it didn't exist.
                 Considered "C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.0\MongoDB.Bson.winmd", but it didn't exist.
                 Considered "C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.0\MongoDB.Bson.dll", but it didn't exist.
                 Considered "C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\v3.0\MongoDB.Bson.exe", but it didn't exist.
                 For SearchPath "{GAC}".

CS proj content:

 <Reference Include="MongoDB.Bson">
      <HintPath>..\packages\mongocsharpdriver.1.9.0\lib\net35\MongoDB.Bson.dll</HintPath>
    </Reference>
    <Reference Include="MongoDB.Driver">
      <HintPath>..\packages\mongocsharpdriver.1.9.0\lib\net35\MongoDB.Driver.dll</HintPath>
    </Reference>

Answer 1

Repointed all the references to the DLL to a folder in the repository rather than GAC, solved my problem.