XnView Software

It depends on what you have. JPEGs? ...anyway, perhaps more details would be better.

Till then, try: in Settings | General -> Rotate images according to EXIF orientation tag

After this, select all thumbs and go to View | Rebuild Thumbnails

Thanks for this information. I had found the option ...

New XnViewMP user here...

I have some images that were rotated 90 degrees by another application.

When I use XnVewMP, the Preview panel shows the image in its correct rotation, but the thumbnails are shown in the original un-rotated orientation.

Is there a setting somewhere that would show ...