BUG: The TransparencyKey property is not effective for Windows forms if the color depth of the monitor is set to a value that is greater than 24-bit

1. Create a sample bitmap file (.bmp) or select a bitmap file that is already available on your computer.
2. Append the following code in the Form1 class constructor after the InitializeComponent statement.
   
   Microsoft Visual Basic .NET or Microsoft Visual Basic 2005 Code

   Dim Img As Bitmap = Bitmap.FromFile("c:\\Example.bmp")
   'The color at Pixel(10,10) is rendered as transparent for the complete background. 
   Img.MakeTransparent(Img.GetPixel(10, 10))
   Me.BackgroundImage = Img
   Me.TransparencyKey = Img.GetPixel(10, 10)

   Microsoft Visual C# .NET or Microsoft Visual C# 2005 Code

   System.Drawing.Bitmap Img = new System.Drawing.Bitmap("c:\\Example.bmp");
   //The color at Pixel(10,10) is rendered as transparent for the complete background. 
   Img.MakeTransparent(Img.GetPixel(10,10));
   this.BackgroundImage = Img;
   this.TransparencyKey = Img.GetPixel(10,10);
   

3. Rebuild the application.

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Steps to Reproduce the Behavior

1. Start Microsoft Visual Studio .NET or Microsoft Visual Studio 2005.
2. On the File menu, point to New, and then click Project.
3. Under Project Types, click Visual Basic Projects or click Visual C# Projects.
   
   Note In Visual Studio 2005, click Visual Basic or Visual C# under Project Types.
4. Under Templates, click Windows Application, and then click OK.
   
   By default, Form1 is added to the project.
5. Right-click Form1, and then click Properties.
6. In the Properties window, set the BackgroundImage property to the background image that you use as the background for the form.
7. Set the TransparencyKey property of Form1 to one of the colors of the background image.
8. On the File menu, click Save All to save the project.
9. On the Debug menu, click Start to run the application.
   
   By default, Form1 appears on the screen. The areas of the form that match the color you set the TransparencyKey property to are not rendered as transparent.

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