Hi Walt,
I do not know the cause of this problem but it must be related to the file thumbs9.vconfig, which is where the viewer's interface settings are stored.
I'd try this:
[*]In TP9, go to
Help | System Info ('Help' is at the far right of the menu)
[*]Note the folder shown as '
Preferences Path' near the bottom of this dialog.
[*]Exit TP9
[*]Open Explorer and go to that folder.
[*]Delete the file
thumbs9.vconfig (or rename it to thumbs9-vconfig.bak)
[*]Re-launch TP9 and open an image to see if the problem is gone now.
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