[Gimp-user] Once opened in Gimp_Ubuntu never to open again

[Carusoswi <forums gimpusers com>]

. . . from Ubuntu, that is.
This is about the development version of Gimp 2.9.1, so if this post belongs
somewhere else, please so inform me and feel free to move it (but please let me
know where it went, LOL).

I right-click on a .tif file (scanned from film), and can open it with any Linux
viewer or photo-editing applicatiion (I have Gimp, of course, Lightzone,
Darktable, PhotoSpot, Irfanview under wine, etc.).

If I open the file with Gimp, I can edit the file, but if I export it as a tif,
the file reports as invalid to all my Linux applications.

I can boot into Win7 and open it with any application there, including Gimp 2.9.

Boot back into Ubuntu, and the file is still invalid.  I have tried this on
several files, result is always the same.

What could possibly be going on?

I know this is a development version of Gimp, so I am not complaining, and,
especially, since the files remain viable in Win7, then, I have a hunch they are
not actually damaged.

I am a software consumer (perhaps with an addiction problem), but have no feel
for programing, so can only be grateful for the wonderful age of nearly
unlimited sources of great software from which to choose, Gimp being one of my
favorites.

Thanks in advance for any advice.

Caruso

-- 
Carusoswi (via www.gimpusers.com/forums)