[tlug] Small detail - file icons

[Dave M G <martin@example.com>]

TLUG,

I'm not sure where the problem here lies, so you may want to tell me to 
take this to a more appropriate forum.
Whenever I download a video, image, PDF, or other graphics related type 
of file, it shows up in my Gnome/Nautilus interface as a nice graphical 
thumbnail icon, showing an image taken from the contents of the file. I 
love that kind of GUI-ness.
However, sometimes I happen to create or download a graphical file 
within my VMWare Player virtual Windows XP.
Then, I copy that file via local "network" to my Linux OS.

When I do that, the file will not have a graphical thumbnail icon, but 
instead a clunky sort of icon in the shape of a page with the top right 
corner folded over (you know the kind) with "AVI" or "PDF" or whatever 
written on it.
Now, if I burn the file down to CD-ROM, then I get the thumbnail icon. 
This is also true if a Windows using friend gives me a CD-ROM or a data 
DVD with graphics on it. Or if I'm emailed something from a Windows user.
I'm denied the thumbnails only when getting a file into my Linux OS when 
it comes via my VMWare Windows XP.
In a way, more than getting these files to display as thumbnails, I'm 
keen to understand the problem in order to understand file formats and 
stuff.
Is the problem Windows? Samba? VMWare? Linux? Gnome? Something else? I 
don't get why it would make a difference to the thumbnailer in Gnome 
where a file came from. Isn't an AVI file an AVI file, wherever it comes 
from?
Please enlighten me, as this is a curious problem.

Thank you for your time and advice.

--
Dave M G