diff --git a/CefSharp.Wpf/Rendering/AbstractRenderHandler.cs b/CefSharp.Wpf/Rendering/AbstractRenderHandler.cs
index 5adbb1b9ac..12ab0b43ac 100644
--- a/CefSharp.Wpf/Rendering/AbstractRenderHandler.cs
+++ b/CefSharp.Wpf/Rendering/AbstractRenderHandler.cs
@@ -20,8 +20,9 @@ namespace CefSharp.Wpf.Rendering
     /// <seealso cref="CefSharp.Wpf.IRenderHandler" />
     public abstract class AbstractRenderHandler : IDisposable, IRenderHandler
     {
-        [DllImport("kernel32.dll", EntryPoint = "CopyMemory", SetLastError = false)]
-        protected static extern void CopyMemory(IntPtr dest, IntPtr src, uint count);
+        // Note: In contrast to RtlMoveMemory, RtlCopyMemory requires that the buffers do not overlap.
+        [DllImport("kernel32.dll", EntryPoint = "RtlCopyMemory", SetLastError = false)]
+        protected static extern void CopyMemory(IntPtr dest, IntPtr src, UIntPtr count);
 
         internal static readonly PixelFormat PixelFormat = PixelFormats.Pbgra32;
         internal static int BytesPerPixel = PixelFormat.BitsPerPixel / 8;
diff --git a/CefSharp.Wpf/Rendering/Experimental/IncreaseBufferInteropRenderHandler.cs b/CefSharp.Wpf/Rendering/Experimental/IncreaseBufferInteropRenderHandler.cs
index d5bcab284d..0d23bc97be 100644
--- a/CefSharp.Wpf/Rendering/Experimental/IncreaseBufferInteropRenderHandler.cs
+++ b/CefSharp.Wpf/Rendering/Experimental/IncreaseBufferInteropRenderHandler.cs
@@ -60,7 +60,7 @@ protected override void CreateOrUpdateBitmap(bool isPopup, Rect dirtyRect, IntPt
 
                 //TODO: Performance analysis to determine which is the fastest memory copy function
                 //NativeMethodWrapper.CopyMemoryUsingHandle(viewAccessor.SafeMemoryMappedViewHandle.DangerousGetHandle(), buffer, numberOfBytes);
-                CopyMemory(viewAccessor.SafeMemoryMappedViewHandle.DangerousGetHandle(), buffer, (uint)numberOfBytes);
+                CopyMemory(viewAccessor.SafeMemoryMappedViewHandle.DangerousGetHandle(), buffer, (UIntPtr)(uint)numberOfBytes);
 
                 //Take a reference to the backBufferHandle, once we're on the UI thread we need to check if it's still valid
                 var backBufferHandle = mappedFile.SafeMemoryMappedFileHandle;
diff --git a/CefSharp.Wpf/Rendering/InteropBitmapRenderHandler.cs b/CefSharp.Wpf/Rendering/InteropBitmapRenderHandler.cs
index c6fbbd3d00..2801d9b206 100644
--- a/CefSharp.Wpf/Rendering/InteropBitmapRenderHandler.cs
+++ b/CefSharp.Wpf/Rendering/InteropBitmapRenderHandler.cs
@@ -54,7 +54,7 @@ protected override void CreateOrUpdateBitmap(bool isPopup, Rect dirtyRect, IntPt
 
                 //TODO: Performance analysis to determine which is the fastest memory copy function
                 //NativeMethodWrapper.CopyMemoryUsingHandle(viewAccessor.SafeMemoryMappedViewHandle.DangerousGetHandle(), buffer, numberOfBytes);
-                CopyMemory(viewAccessor.SafeMemoryMappedViewHandle.DangerousGetHandle(), buffer, (uint)numberOfBytes);
+                CopyMemory(viewAccessor.SafeMemoryMappedViewHandle.DangerousGetHandle(), buffer, (UIntPtr)(uint)numberOfBytes);
 
                 //Take a reference to the backBufferHandle, once we're on the UI thread we need to check if it's still valid
                 var backBufferHandle = mappedFile.SafeMemoryMappedFileHandle;
diff --git a/CefSharp.Wpf/Rendering/WritableBitmapRenderHandler.cs b/CefSharp.Wpf/Rendering/WritableBitmapRenderHandler.cs
index 84941e9935..d4da4e4016 100644
--- a/CefSharp.Wpf/Rendering/WritableBitmapRenderHandler.cs
+++ b/CefSharp.Wpf/Rendering/WritableBitmapRenderHandler.cs
@@ -64,7 +64,7 @@ protected override void CreateOrUpdateBitmap(bool isPopup, Rect dirtyRect, IntPt
 
                 //TODO: Performance analysis to determine which is the fastest memory copy function
                 //NativeMethodWrapper.CopyMemoryUsingHandle(viewAccessor.SafeMemoryMappedViewHandle.DangerousGetHandle(), buffer, numberOfBytes);
-                CopyMemory(viewAccessor.SafeMemoryMappedViewHandle.DangerousGetHandle(), buffer, (uint)numberOfBytes);
+                CopyMemory(viewAccessor.SafeMemoryMappedViewHandle.DangerousGetHandle(), buffer, (UIntPtr)(uint)numberOfBytes);
 
                 //Take a reference to the sourceBuffer that's used to update our WritableBitmap,
                 //once we're on the UI thread we need to check if it's still valid