diff --git a/src/Compilers/Extension/CompilerExtension.csproj b/src/Compilers/Extension/CompilerExtension.csproj
index 4537bab2ffe882206dea4cebe55768122b915eb3..8f869e1a9c71821a545447be72841dd94c2d37bf 100644
--- a/src/Compilers/Extension/CompilerExtension.csproj
+++ b/src/Compilers/Extension/CompilerExtension.csproj
@@ -102,6 +102,7 @@
       <IncludeOutputGroupsInVSIX>BuiltProjectOutputGroup</IncludeOutputGroupsInVSIX>
       <IncludeOutputGroupsInVSIXLocalOnly>DebugSymbolsProjectOutputGroup%3b</IncludeOutputGroupsInVSIXLocalOnly>
       <ForceIncludeInVSIX>true</ForceIncludeInVSIX>
+      <!-- Workaround for https://github.com/dotnet/sdk/issues/433#issuecomment-320024771 . Remove once resolved. -->
       <AdditionalProperties>TargetFramework=net46</AdditionalProperties>
     </ProjectReference>
     <ProjectReference Include="..\CSharp\csc\csc.csproj">
diff --git a/src/Compilers/Server/VBCSCompiler/CoreClrCompilerServerHost.cs b/src/Compilers/Server/VBCSCompiler/CoreClrCompilerServerHost.cs
new file mode 100644
index 0000000000000000000000000000000000000000..af47e77814b5ae546d6ffc6bbb16c533770b97fe
--- /dev/null
+++ b/src/Compilers/Server/VBCSCompiler/CoreClrCompilerServerHost.cs
@@ -0,0 +1,33 @@
+// Copyright (c) Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information.
+
+#if NETCOREAPP2_0
+
+using System;
+using System.Collections.Immutable;
+
+namespace Microsoft.CodeAnalysis.CompilerServer
+{
+    internal sealed class CoreClrCompilerServerHost : CompilerServerHost
+    {
+        private static readonly IAnalyzerAssemblyLoader s_analyzerLoader = new CoreClrAnalyzerAssemblyLoader();
+
+        // Caches are used by C# and VB compilers, and shared here.
+        public static readonly Func<string, MetadataReferenceProperties, PortableExecutableReference> SharedAssemblyReferenceProvider = (path, properties) => new CachingMetadataReference(path, properties);
+
+        public override IAnalyzerAssemblyLoader AnalyzerAssemblyLoader => s_analyzerLoader;
+
+        public override Func<string, MetadataReferenceProperties, PortableExecutableReference> AssemblyReferenceProvider => SharedAssemblyReferenceProvider;
+
+        internal CoreClrCompilerServerHost(string clientDirectory, string sdkDirectory)
+            : base(clientDirectory, sdkDirectory)
+        {
+        }
+
+        public override bool CheckAnalyzers(string baseDirectory, ImmutableArray<CommandLineAnalyzerReference> analyzers)
+        {
+            return AnalyzerConsistencyChecker.Check(baseDirectory, analyzers, s_analyzerLoader);
+        }
+    }
+}
+
+#endif
diff --git a/src/Compilers/Server/VBCSCompiler/DesktopBuildServerController.cs b/src/Compilers/Server/VBCSCompiler/DesktopBuildServerController.cs
index 0e5c32c19a138eac8add8e798259a7492ed81672..8145a77d7bdc904f2b8ac70126b89c8fc0004bfa 100644
--- a/src/Compilers/Server/VBCSCompiler/DesktopBuildServerController.cs
+++ b/src/Compilers/Server/VBCSCompiler/DesktopBuildServerController.cs
@@ -40,23 +40,31 @@ protected override IClientConnectionHost CreateClientConnectionHost(string pipeN
 
         protected internal override TimeSpan? GetKeepAliveTimeout()
         {
-            int keepAliveValue;
-            string keepAliveStr = _appSettings[KeepAliveSettingName];
-            if (int.TryParse(keepAliveStr, NumberStyles.Integer, CultureInfo.InvariantCulture, out keepAliveValue) &&
-                keepAliveValue >= 0)
+            try
             {
-                if (keepAliveValue == 0)
+                int keepAliveValue;
+                string keepAliveStr = _appSettings[KeepAliveSettingName];
+                if (int.TryParse(keepAliveStr, NumberStyles.Integer, CultureInfo.InvariantCulture, out keepAliveValue) &&
+                    keepAliveValue >= 0)
                 {
-                    // This is a one time server entry.
-                    return null;
+                    if (keepAliveValue == 0)
+                    {
+                        // This is a one time server entry.
+                        return null;
+                    }
+                    else
+                    {
+                        return TimeSpan.FromSeconds(keepAliveValue);
+                    }
                 }
                 else
                 {
-                    return TimeSpan.FromSeconds(keepAliveValue);
+                    return ServerDispatcher.DefaultServerKeepAlive;
                 }
             }
-            else
+            catch (Exception e)
             {
+                CompilerServerLogger.LogException(e, "Could not read AppSettings");
                 return ServerDispatcher.DefaultServerKeepAlive;
             }
         }