Use checked-in key to build ReleaseSigned
diff --git a/csharp/src/Google.Protobuf.Test/Google.Protobuf.Test.csproj b/csharp/src/Google.Protobuf.Test/Google.Protobuf.Test.csproj
index 20ae8e4..4f37c5e 100644
--- a/csharp/src/Google.Protobuf.Test/Google.Protobuf.Test.csproj
+++ b/csharp/src/Google.Protobuf.Test/Google.Protobuf.Test.csproj
@@ -55,7 +55,7 @@
     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>

     <Prefer32Bit>false</Prefer32Bit>

     <SignAssembly>True</SignAssembly>

-    <AssemblyOriginatorKeyFile>C:\keys\Google.Protobuf.snk</AssemblyOriginatorKeyFile>

+    <AssemblyOriginatorKeyFile>..\..\keys\Google.Protobuf.snk</AssemblyOriginatorKeyFile>

   </PropertyGroup>

   <ItemGroup>

     <Reference Include="mscorlib" />

diff --git a/csharp/src/Google.Protobuf/Google.Protobuf.csproj b/csharp/src/Google.Protobuf/Google.Protobuf.csproj
index 45ef8c6..ef524ba 100644
--- a/csharp/src/Google.Protobuf/Google.Protobuf.csproj
+++ b/csharp/src/Google.Protobuf/Google.Protobuf.csproj
@@ -64,7 +64,7 @@
     <NoStdLib>true</NoStdLib>

     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>

     <SignAssembly>True</SignAssembly>

-    <AssemblyOriginatorKeyFile>C:\keys\Google.Protobuf.snk</AssemblyOriginatorKeyFile>

+    <AssemblyOriginatorKeyFile>..\..\keys\Google.Protobuf.snk</AssemblyOriginatorKeyFile>

     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>

   </PropertyGroup>

   <ItemGroup>