Use the Static Picturebox (StaticPicture) control to show pictures in the feature class form, for example, your company logo.
Although the picture files can be stored in any folder, it is recommended that you store them in the <Infrastructure Map Server>\Pics folder or a subfolder. Then, they are available with the dynamic path <Infrastructure Map Server>\Pics and you need to enter the subfolder/filename only. If you use picture files with a static path, they are not available on a different computer unless the path is exactly the same. Alternatively, you can use //Servername to store the picture files on a server.
To show the pictures both in Infrastructure Map Server and Infrastructure Application Extension , make sure that the pictures are stored both in the <Infrastructure Map Server>\Pics folder and the <Infrastructure Application Extension>Pics folder or subfolder.