diff --git a/src/VisualStudio/Core/Def/ProjectSystem/CPS/IWorkspaceProjectContextFactory.cs b/src/VisualStudio/Core/Def/ProjectSystem/CPS/IWorkspaceProjectContextFactory.cs
index 9bc7159e1e56e..98f3094bee6d8 100644
--- a/src/VisualStudio/Core/Def/ProjectSystem/CPS/IWorkspaceProjectContextFactory.cs
+++ b/src/VisualStudio/Core/Def/ProjectSystem/CPS/IWorkspaceProjectContextFactory.cs
@@ -15,29 +15,6 @@ namespace Microsoft.VisualStudio.LanguageServices.ProjectSystem;
 /// </summary>
 internal interface IWorkspaceProjectContextFactory
 {
-    /// <summary>
-    /// Creates and initializes a new Workspace project and returns a <see
-    /// cref="IWorkspaceProjectContext"/> to lazily initialize the properties and items for the
-    /// project.  This method guarantees that either the project is added (and the returned task
-    /// completes) or cancellation is observed and no project is added.
-    /// </summary>
-    /// <param name="languageName">Project language.</param>
-    /// <param name="projectUniqueName">Unique name for the project.</param>
-    /// <param name="projectFilePath">Full path to the project file for the project.</param>
-    /// <param name="projectGuid">Project guid.</param>
-    /// <param name="hierarchy">The IVsHierarchy for the project; this is used to track linked files across multiple projects when determining contexts.</param>
-    /// <param name="binOutputPath">Initial project binary output path.</param>
-    [Obsolete]
-    Task<IWorkspaceProjectContext> CreateProjectContextAsync(
-        string languageName,
-        string projectUniqueName,
-        string projectFilePath,
-        Guid projectGuid,
-        object? hierarchy,
-        string? binOutputPath,
-        string? assemblyName,
-        CancellationToken cancellationToken);
-
     /// <summary>
     /// Creates and initializes a new project and returns a <see
     /// cref="IWorkspaceProjectContext"/> to lazily initialize the properties and items for the
diff --git a/src/VisualStudio/Core/Impl/ProjectSystem/CPS/CPSProjectFactory.cs b/src/VisualStudio/Core/Impl/ProjectSystem/CPS/CPSProjectFactory.cs
index 7abe1ea5cdef9..32b413a3d2dd4 100644
--- a/src/VisualStudio/Core/Impl/ProjectSystem/CPS/CPSProjectFactory.cs
+++ b/src/VisualStudio/Core/Impl/ProjectSystem/CPS/CPSProjectFactory.cs
@@ -57,58 +57,6 @@ public ImmutableArray<string> EvaluationPropertyNames
     public ImmutableArray<string> EvaluationItemNames
         => BuildPropertyNames.InitialEvaluationItemNames;
 
-    // Kept around onyl for integration tests.
-    [Obsolete]
-    public Task<IWorkspaceProjectContext> CreateProjectContextAsync(
-        string languageName,
-        string projectUniqueName,
-        string? projectFilePath,
-        Guid projectGuid,
-        object? hierarchy,
-        string? binOutputPath,
-        string? assemblyName,
-        CancellationToken cancellationToken)
-    {
-        var data = new IntegrationTestEvaluationData(projectFilePath ?? "", projectFilePath ?? "", assemblyName ?? "", binOutputPath ?? "", "SHA256");
-        return CreateProjectContextAsync(projectGuid, projectUniqueName, languageName, data, hierarchy, cancellationToken);
-    }
-
-    [Obsolete]
-    internal sealed class IntegrationTestEvaluationData : EvaluationData
-    {
-        public string ProjectFilePath { get; }
-        public string TargetPath { get; }
-        public string AssemblyName { get; }
-        public string OutputAssembly { get; }
-        public string ChecksumAlgorithm { get; }
-
-        public IntegrationTestEvaluationData(string projectFilePath, string targetPath, string assemblyName, string outputAssembly, string checksumAlgorithm)
-        {
-            ProjectFilePath = projectFilePath;
-            TargetPath = targetPath;
-            AssemblyName = assemblyName;
-            OutputAssembly = outputAssembly;
-            ChecksumAlgorithm = checksumAlgorithm;
-        }
-
-        public override string GetPropertyValue(string name)
-            => name switch
-            {
-                BuildPropertyNames.MSBuildProjectFullPath => ProjectFilePath,
-                BuildPropertyNames.TargetPath => TargetPath,
-                BuildPropertyNames.AssemblyName => AssemblyName,
-                BuildPropertyNames.CommandLineArgsForDesignTimeEvaluation => "-checksumalgorithm:" + ChecksumAlgorithm,
-                _ => throw ExceptionUtilities.UnexpectedValue(name)
-            };
-
-        public override ImmutableArray<string> GetItemValues(string name)
-            => name switch
-            {
-                BuildPropertyNames.IntermediateAssembly => [OutputAssembly],
-                _ => throw ExceptionUtilities.UnexpectedValue(name)
-            };
-    }
-
     public async Task<IWorkspaceProjectContext> CreateProjectContextAsync(Guid id, string uniqueName, string languageName, EvaluationData data, object? hostObject, CancellationToken cancellationToken)
     {
         // Read all required properties from EvaluationData before we start updating anything.
@@ -203,11 +151,13 @@ public async Task<IWorkspaceProjectContext> CreateProjectContextAsync(Guid id, s
         const string itemName = BuildPropertyNames.IntermediateAssembly;
 
         var values = data.GetItemValues(itemName);
-        if (values.Length != 1)
+        if (values.Length > 1)
+        {
+            var joinedValues = string.Join(";", values);
+            throw new InvalidProjectDataException(itemName, joinedValues, $"Item group '{itemName}' is required to specify a single value: '{joinedValues}'.");
+        }
+        else if (values.Length == 0)
         {
-            // TODO: Throw once we update integration tests to the latest VS (https://github.com/dotnet/roslyn/issues/65439)
-            // var joinedValues = string.Join(";", values);
-            // throw new InvalidProjectDataException(itemName, joinedValues, $"Item group '{itemName}' is required to specify a single value: '{joinedValues}'.");
             return null;
         }