diff --git a/eng/Directory.Packages.props b/eng/Directory.Packages.props
index 322e86f7aac7d..af74dd6b283d6 100644
--- a/eng/Directory.Packages.props
+++ b/eng/Directory.Packages.props
@@ -182,6 +182,7 @@
     <PackageVersion Include="Microsoft.NETFramework.ReferenceAssemblies.net472" Version="1.0.3" />
     <PackageVersion Include="Microsoft.NETFramework.ReferenceAssemblies.net461" Version="1.0.3" />
     <PackageVersion Include="Microsoft.NETFramework.ReferenceAssemblies.net451" Version="1.0.3" />
+    <PackageVersion Include="Microsoft.NETFramework.ReferenceAssemblies.net45" Version="1.0.3" />
     <PackageVersion Include="Microsoft.NETFramework.ReferenceAssemblies.net40" Version="1.0.3" />
     <PackageVersion Include="Microsoft.NETFramework.ReferenceAssemblies.net20" Version="1.0.3" />
     <PackageVersion Include="System.Buffers" Version="4.5.1" />
diff --git a/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/PackAllRids.targets b/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/PackAllRids.targets
index 3618fecc0b7ab..53ced13fbc184 100644
--- a/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/PackAllRids.targets
+++ b/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/PackAllRids.targets
@@ -29,4 +29,10 @@
 
     <MSBuild Projects="@(ProjectToPublish)" Targets="Pack" BuildInParallel="true" />
   </Target>
+
+  <!--
+    Make sure the _GetPackageFiles target exists, since it is always expected for design time builds, but only
+    defined when ImportNuGetBuildTasksPackTargetsFromSdk is true.
+  -->
+  <Target Name="_GetPackageFiles" />
 </Project>
diff --git a/src/Tools/SemanticSearch/ReferenceAssemblies/SemanticSearch.ReferenceAssemblies.csproj b/src/Tools/SemanticSearch/ReferenceAssemblies/SemanticSearch.ReferenceAssemblies.csproj
index 0ff3c9cb5533c..12f985c4d121b 100644
--- a/src/Tools/SemanticSearch/ReferenceAssemblies/SemanticSearch.ReferenceAssemblies.csproj
+++ b/src/Tools/SemanticSearch/ReferenceAssemblies/SemanticSearch.ReferenceAssemblies.csproj
@@ -5,6 +5,7 @@
 
     <_BuildTaskTfm Condition="'$(MSBuildRuntimeType)' != 'Core'">net472</_BuildTaskTfm>
     <_BuildTaskTfm Condition="'$(MSBuildRuntimeType)' == 'Core'">$(NetRoslyn)</_BuildTaskTfm>
+    <_BuildTaskAssemblyFile>$(ArtifactsBinDir)SemanticSearch.BuildTask\$(Configuration)\$(_BuildTaskTfm)\SemanticSearch.BuildTask.dll</_BuildTaskAssemblyFile>
   </PropertyGroup>
 
   <ItemGroup>
@@ -26,7 +27,7 @@
     in subsequent builds because the task assembly can't be written by the
     next build.
   -->
-  <UsingTask TaskName="Microsoft.CodeAnalysis.Tools.GenerateFilteredReferenceAssembliesTask" AssemblyFile="$(ArtifactsBinDir)SemanticSearch.BuildTask\$(Configuration)\$(_BuildTaskTfm)\SemanticSearch.BuildTask.dll" TaskFactory="TaskHostFactory" />
+  <UsingTask TaskName="Microsoft.CodeAnalysis.Tools.GenerateFilteredReferenceAssembliesTask" AssemblyFile="$(_BuildTaskAssemblyFile)" TaskFactory="TaskHostFactory" />
 
   <Target Name="_CalculateFilteredReferenceAssembliesInputsAndOutputs" DependsOnTargets="ResolveAssemblyReferences">
     <PropertyGroup>
@@ -49,7 +50,7 @@
     </ItemGroup>
   </Target>
   
-  <Target Name="GenerateFilteredReferenceAssemblies" BeforeTargets="CoreCompile" DependsOnTargets="_CalculateFilteredReferenceAssembliesInputsAndOutputs" Inputs="@(_InputFile)" Outputs="@(_OutputFile)">
+  <Target Name="GenerateFilteredReferenceAssemblies" Condition="Exists('$(_BuildTaskAssemblyFile)')" BeforeTargets="CoreCompile" DependsOnTargets="_CalculateFilteredReferenceAssembliesInputsAndOutputs" Inputs="@(_InputFile)" Outputs="@(_OutputFile)">
 
     <MakeDir Directories="$(_OutputDir)" />
     <Microsoft.CodeAnalysis.Tools.GenerateFilteredReferenceAssembliesTask References="@(_InputReference)" ApiSets="@(ApiSet)" OutputDir="$(_OutputDir)" />
diff --git a/src/VisualStudio/IntegrationTest/IntegrationTestBuildProject.csproj b/src/VisualStudio/IntegrationTest/IntegrationTestBuildProject.csproj
index fd37008e6ce7e..ed2f2c6590b3d 100644
--- a/src/VisualStudio/IntegrationTest/IntegrationTestBuildProject.csproj
+++ b/src/VisualStudio/IntegrationTest/IntegrationTestBuildProject.csproj
@@ -1,8 +1,13 @@
 <Project Sdk="Microsoft.Build.Traversal">
   <PropertyGroup>
-   <TargetFrameworks>net472</TargetFrameworks>
+    <TargetFrameworks>net472</TargetFrameworks>
     <ExcludeFromSourceBuild>true</ExcludeFromSourceBuild>
   </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NETFramework.ReferenceAssemblies.net45" />
+  </ItemGroup>
+
   <!--
     This build project is used to allow CI to only build the projects required to build and run integration tests.
     Everything else (for example other unit test projects) are excluded to speed up the build time.