[Paint.net 4.3 no longer appears in the "Open with" drop down list]

Almost all types of image files are affected by this behavior. The typical image and graphic file extensions which are often found associated with Windows Paint (I'm using Windows 7) and other similar programs cannot be opened with Paint.Net by right-clicking the file and choosing "Open with" from the drop down menu. The exceptions are GIF, BMP and DIB. The uploaded image shows what is displayed when right-clicking of a JPG file. Paint.net is missing from the list.

[Paint.net 4.3 no longer appears in the "Open with" drop down list]

If you right-click an image file and drill down to "Open with", paint.net is not present in the list of graphics programs as it was in version 4.2.