[Gimp-user] Problem saving in PNG format

[John Williams <jdw space gmail com>]

Hi,
  I have been using GIMP to save image files in the .png format for many
years.  I recently upgraded to GIMP 2.8 and I cannot seem to save/export
the image files.  This is not about what kind of command I am using or
whether or not the user interface is good or bad.  When I activate the
export command I successfully complete the process without any error
message.
  I am using the .png image files as wallpapers for the fvwm window manager
and I get no error messages or any indication that something is wrong, I
just get no wallpaper image.  (Please refrain from commenting about the
dinosaur-ness of my window manager;))
  I have searched the FAQ and gimp user archives but cannot seem to find
any mention of this problem.
  I have also made sure that I have merged and/or flattened the images and
have also used the convert tool to use the sRGB color profile.  I also have
the file-png plugin loaded in my plug-in directory.  None of these options
have made a difference.
  Does anyone know anything about this kind of problem?  Does anyone know
where I might find information about how to fix this kind of problem?
Thanks very much for your assistance.
John