diagram.CreateImage(); creating an empty image.
This is my code:

using (MemoryStream ms2 = new MemoryStream(Process.ReadProcessDiagram(ProcessID)))
            {
                XmlDocument doc = new XmlDocument();
                doc.Load(ms2);
                diagram.LoadFromXml(doc);
                var diagramImage = diagram.CreateImage();

                CreateImageFile(diagramImage,  "D:\\diagram1.jpg");
            }


private static void CreateImageFile(BitmapSource source, string imageFileName)
        {
            // add the RenderTargetBitmap to a Bitmapencoder
            PngBitmapEncoder encoder = new PngBitmapEncoder();
            var bitmapFrame = BitmapFrame.Create(source);

            encoder.Frames.Add(bitmapFrame);

            using (MemoryStream ms = new MemoryStream())
            {
                encoder.Save(ms);

                System.Drawing.Bitmap bitmap = new System.Drawing.Bitmap(ms);

                if (WorkflowHelper.IsRightToLeft)
                    bitmap.RotateFlip(System.Drawing.RotateFlipType.Rotate180FlipY);
                bitmap.Save(imageFileName);
                ms.Close();
            }
        }

Any help please!!

I added this line of code and nothing changed. The attached image is the result.

Same result. I tried to save another image in the same way and it worked fine. So, I think the problem is in the CreateImage method. Please try my code or send me a small tested code that creates an image from a diagram (in WPF) and save it as an image file.
Note: I used the same method in the Windows Forms version and it is working there.

It worked. Thank you