diff --git a/eng/Common.globalconfig b/eng/Common.globalconfig
index 16b2b818ed0..2239db9472e 100644
--- a/eng/Common.globalconfig
+++ b/eng/Common.globalconfig
@@ -901,7 +901,7 @@ dotnet_diagnostic.SA1217.severity = suggestion
 dotnet_diagnostic.SA1300.severity = suggestion
 
 # Interface names should begin with I
-dotnet_diagnostic.SA1302.severity = suggestion
+dotnet_diagnostic.SA1302.severity = warning
 
 # Const field names should begin with upper-case letter
 dotnet_diagnostic.SA1303.severity = suggestion
diff --git a/src/Build.OM.UnitTests/Definition/ProjectItem_Tests.cs b/src/Build.OM.UnitTests/Definition/ProjectItem_Tests.cs
index 646502ad240..2d1bf2a724a 100644
--- a/src/Build.OM.UnitTests/Definition/ProjectItem_Tests.cs
+++ b/src/Build.OM.UnitTests/Definition/ProjectItem_Tests.cs
@@ -3454,7 +3454,7 @@ public void UpdateAndRemoveShouldNotUseGlobMatchingOnEscapedGlobsFromReferencedI
                     return new Project(p, new Dictionary<string, string>(), MSBuildConstants.CurrentToolsVersion, c)
                         .Items
                         .Where(i => i.ItemType.Equals("i"))
-                        .Select(i => (ObjectModelHelpers.TestItem)new ObjectModelHelpers.ProjectItemTestItemAdapter(i))
+                        .Select(i => (ObjectModelHelpers.ITestItem)new ObjectModelHelpers.ProjectItemTestItemAdapter(i))
                         .ToList();
                 },
                 project,
diff --git a/src/Build.UnitTests/BackEnd/IntrinsicTask_Tests.cs b/src/Build.UnitTests/BackEnd/IntrinsicTask_Tests.cs
index 818aea598e1..a22156f33f0 100644
--- a/src/Build.UnitTests/BackEnd/IntrinsicTask_Tests.cs
+++ b/src/Build.UnitTests/BackEnd/IntrinsicTask_Tests.cs
@@ -3927,7 +3927,7 @@ internal static void AssertItemEvaluationFromTarget(string projectContents, stri
                     var lookup = new Lookup(new ItemDictionary<ProjectItemInstance>(), new PropertyDictionary<ProjectPropertyInstance>());
                     task.ExecuteTask(lookup);
 
-                    return lookup.GetItems(itemType).Select(i => (ObjectModelHelpers.TestItem)new ObjectModelHelpers.ProjectItemInstanceTestItemAdapter(i)).ToList();
+                    return lookup.GetItems(itemType).Select(i => (ObjectModelHelpers.ITestItem)new ObjectModelHelpers.ProjectItemInstanceTestItemAdapter(i)).ToList();
                 },
                 projectContents,
                 inputFiles,
diff --git a/src/Shared/UnitTests/ObjectModelHelpers.cs b/src/Shared/UnitTests/ObjectModelHelpers.cs
index f97a38f3ba2..d6c10b453e0 100644
--- a/src/Shared/UnitTests/ObjectModelHelpers.cs
+++ b/src/Shared/UnitTests/ObjectModelHelpers.cs
@@ -122,7 +122,7 @@ internal static void AssertItemEvaluationFromProject(string projectContents, str
                 {
                     return new Project(p, new Dictionary<string, string>(), MSBuildConstants.CurrentToolsVersion, c)
                         .Items
-                        .Select(i => (TestItem)new ProjectItemTestItemAdapter(i))
+                        .Select(i => (ITestItem)new ProjectItemTestItemAdapter(i))
                         .ToList();
                 },
             projectContents,
@@ -133,7 +133,7 @@ internal static void AssertItemEvaluationFromProject(string projectContents, str
             normalizeSlashes);
         }
 
-        internal static void AssertItemEvaluationFromGenericItemEvaluator(Func<string, ProjectCollection, IList<TestItem>> itemEvaluator, string projectContents, string[] inputFiles, string[] expectedInclude, bool makeExpectedIncludeAbsolute = false, Dictionary<string, string>[] expectedMetadataPerItem = null, bool normalizeSlashes = false)
+        internal static void AssertItemEvaluationFromGenericItemEvaluator(Func<string, ProjectCollection, IList<ITestItem>> itemEvaluator, string projectContents, string[] inputFiles, string[] expectedInclude, bool makeExpectedIncludeAbsolute = false, Dictionary<string, string>[] expectedMetadataPerItem = null, bool normalizeSlashes = false)
         {
             using (var env = TestEnvironment.Create())
             using (var collection = new ProjectCollection())
@@ -197,14 +197,14 @@ internal static string NormalizeSlashes(string path)
         }
 
         // todo Make IItem<M> public and add these new members to it.
-        internal interface TestItem
+        internal interface ITestItem
         {
             string EvaluatedInclude { get; }
             int DirectMetadataCount { get; }
             string GetMetadataValue(string key);
         }
 
-        internal class ProjectItemTestItemAdapter : TestItem
+        internal class ProjectItemTestItemAdapter : ITestItem
         {
             private readonly ProjectItem _projectInstance;
 
@@ -223,7 +223,7 @@ public static implicit operator ProjectItemTestItemAdapter(ProjectItem pi)
             }
         }
 
-        internal class ProjectItemInstanceTestItemAdapter : TestItem
+        internal class ProjectItemInstanceTestItemAdapter : ITestItem
         {
             private readonly ProjectItemInstance _projectInstance;
 
@@ -244,14 +244,14 @@ public static implicit operator ProjectItemInstanceTestItemAdapter(ProjectItemIn
 
         internal static void AssertItems(string[] expectedItems, ICollection<ProjectItem> items, Dictionary<string, string> expectedDirectMetadata = null, bool normalizeSlashes = false)
         {
-            var converteditems = items.Select(i => (TestItem)new ProjectItemTestItemAdapter(i)).ToList();
+            var converteditems = items.Select(i => (ITestItem)new ProjectItemTestItemAdapter(i)).ToList();
             AssertItems(expectedItems, converteditems, expectedDirectMetadata, normalizeSlashes);
         }
 
         /// <summary>
         /// Asserts that the list of items has the specified evaluated includes.
         /// </summary>
-        internal static void AssertItems(string[] expectedItems, IList<TestItem> items, Dictionary<string, string> expectedDirectMetadata = null, bool normalizeSlashes = false)
+        internal static void AssertItems(string[] expectedItems, IList<ITestItem> items, Dictionary<string, string> expectedDirectMetadata = null, bool normalizeSlashes = false)
         {
             if (expectedDirectMetadata == null)
             {
@@ -271,11 +271,11 @@ internal static void AssertItems(string[] expectedItems, IList<TestItem> items,
 
         public static void AssertItems(string[] expectedItems, IList<ProjectItem> items, Dictionary<string, string>[] expectedDirectMetadataPerItem, bool normalizeSlashes = false)
         {
-            var convertedItems = items.Select(i => (TestItem)new ProjectItemTestItemAdapter(i)).ToList();
+            var convertedItems = items.Select(i => (ITestItem)new ProjectItemTestItemAdapter(i)).ToList();
             AssertItems(expectedItems, convertedItems, expectedDirectMetadataPerItem, normalizeSlashes);
         }
 
-        public static void AssertItems(string[] expectedItems, IList<TestItem> items, Dictionary<string, string>[] expectedDirectMetadataPerItem, bool normalizeSlashes = false)
+        public static void AssertItems(string[] expectedItems, IList<ITestItem> items, Dictionary<string, string>[] expectedDirectMetadataPerItem, bool normalizeSlashes = false)
         {
             if (items.Count != 0 || expectedDirectMetadataPerItem.Length != 0)
             {
@@ -467,7 +467,7 @@ internal static void AssertItemHasMetadata(string key, string value, ProjectItem
             item.GetMetadataValue(key).ShouldBe(value);
         }
 
-        internal static void AssertItemHasMetadata(Dictionary<string, string> expected, TestItem item)
+        internal static void AssertItemHasMetadata(Dictionary<string, string> expected, ITestItem item)
         {
             expected ??= new Dictionary<string, string>();
 
diff --git a/src/Tasks/NativeMethods.cs b/src/Tasks/NativeMethods.cs
index e2cdca0cc3b..48f3d17926a 100644
--- a/src/Tasks/NativeMethods.cs
+++ b/src/Tasks/NativeMethods.cs
@@ -57,7 +57,7 @@ public interface IFixedTypeInfo
     [GuidAttribute("00020406-0000-0000-C000-000000000046")]
     [InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
     [ComImport]
-    internal interface UCOMICreateITypeLib
+    internal interface ICreateTypeLib
     {
         void CreateTypeInfo();
         void SetName();
diff --git a/src/Tasks/RegisterAssembly.cs b/src/Tasks/RegisterAssembly.cs
index 0416f291811..a7b6a78edf4 100644
--- a/src/Tasks/RegisterAssembly.cs
+++ b/src/Tasks/RegisterAssembly.cs
@@ -343,7 +343,7 @@ private bool ExportTypeLib(Assembly asm, string typeLibFileName)
                 }
 
                 // Persist the type library
-                UCOMICreateITypeLib createTypeLib = (UCOMICreateITypeLib)convertedTypeLib;
+                ICreateTypeLib createTypeLib = (ICreateTypeLib)convertedTypeLib;
 
                 createTypeLib.SaveAllChanges();
             }