diff --git a/MimeKit/MimeKit.Portable.csproj b/MimeKit/MimeKit.Portable.csproj
index 5d9b006c4b..76b09bedc0 100644
--- a/MimeKit/MimeKit.Portable.csproj
+++ b/MimeKit/MimeKit.Portable.csproj
@@ -236,11 +236,6 @@
     <Compile Include="TextPart.cs" />
     <Compile Include="XPriority.cs" />
   </ItemGroup>
-  <ItemGroup>
-    <Reference Include="crypto">
-      <HintPath>..\packages\Portable.BouncyCastle.1.8.1\lib\portable-net45+win8+wpa81+MonoTouch10+MonoAndroid10+xamarinmac20+xamarinios10\crypto.dll</HintPath>
-    </Reference>
-  </ItemGroup>
   <ItemGroup>
     <None Include="packages.MimeKit.Portable.config" />
   </ItemGroup>
diff --git a/MimeKit/MimeKit.WindowsUniversal81.csproj b/MimeKit/MimeKit.WindowsUniversal81.csproj
index 3e70dd40ad..2ada6f2cc8 100644
--- a/MimeKit/MimeKit.WindowsUniversal81.csproj
+++ b/MimeKit/MimeKit.WindowsUniversal81.csproj
@@ -242,11 +242,6 @@
     <Compile Include="TextPart.cs" />
     <Compile Include="XPriority.cs" />
   </ItemGroup>
-  <ItemGroup>
-    <Reference Include="crypto">
-      <HintPath>..\packages\Portable.BouncyCastle.1.8.1\lib\portable-net45+win8+wpa81+MonoTouch10+MonoAndroid10+xamarinmac20+xamarinios10\crypto.dll</HintPath>
-    </Reference>
-  </ItemGroup>
   <ItemGroup>
     <None Include="packages.MimeKit.WindowsUniversal81.config" />
   </ItemGroup>