Thumbnails in wrong Orientation

[infosauger]

Hello,

I have old files that have no EXIF-Information and are displayed in the wrong orientation. Therefor I added EXIF-Orientation with Exif Pilot.
Windows Explorer dsiplays the Images correct according the new EXIF-Information.

In XnViewMP the Images aren't displayed correctly! See Original.JPG.
After "Rebuild thumbnails" the Images with the new EXIF-Information are display in the right orientation. They also have the orientation symbol.
See AfterRebuild.JPG
BUT:
When I browse to another folder and back to this one, the images are displayed wrong again! I don't know why XnView dowsn't remember the correct thumbnails!
When I browse to a folder with newer files that have EXIF-Orientation Information too, there the images are displayed correct.

I tried restart the program and even rebuild thumbnails in catalog settings. No success.

[xnview]

could you send me a file sample?

[infosauger]

I'll try, but the files I have are too large. I don't know what happens If I reduce their size with XnViewMP too.

UPDATE:
I tried to resize one of the pictures to upload it. But after resizing it with XNViewMP the picture has EXIF-Information. After assigning orientation information to both files, only the thumbnail of the resized one is always correctly displayed.

UPDATE 2:
I uploaded the files:
This is the original Picture without any EXIF-Information:
https://1drv.ms/u/s!AgLIdzqK56rakkS11Rk ... 3?e=60Wb9C

This is the File with Added EXIF-Orientation:
https://1drv.ms/u/s!AgLIdzqK56rakkXWfF6 ... N?e=WvaLnN

[xnview]

This is the original Picture without any EXIF-Information:
https://1drv.ms/u/s!AgLIdzqK56rakkS11Rk ... 3?e=60Wb9C

It's normal, this file is portrait not landscape, there is no way to know the orientation

[infosauger]

It's normal, this file is portrait not landscape, there is no way to know the orientation

You are right for this picture.
However, I added the orientation Info in the other one and it is still shown in portrait until I rebuild thumbnails. When I change to a different folder and back to this folder, the second picture with Orientation Info is shown as portrait again until I rebuild thumbnails again.
Windows explorer shows the picture with orientation Info always correctly as landscape.
Gimp detects the orientation info too and displays the picture in landscape.
In XnViewMP I have to rebuild thumbnail each time I navigate to this folder to display this picture and others correctly.

[xnview]

the version with EXIF is correctly oriented, in landscape...

[infosauger]

the version with EXIF is correctly oriented, in landscape...

Interesting,
I don't see it in landscape in the thumbnails. I have to rebuild thumbnails to see it correctly.
In the preview window it's always shown in landscape.
So there is something wrong with settings. But witch one. Newer pictures with orientation info are shown correctly.

[xnview]

I don't see it in landscape in the thumbnails. I have to rebuild thumbnails to see it correctly.

So it is correct after rebuilding?

[infosauger]

So it is correct after rebuilding?

Yes, but if I browse to another folder and back to this one, I have to rebuild again.
But it has nothing to do with the folder itself. When I move/copy the pictures in a completly new folder, it happens there too.
I removed the folder from the catalogue, but this still happens.
I rebuilt thumbnails from the catalogue settings, but that didn't help at all. The picture stays portrait. I have to rebuild thumbnails in the browser view, with View-> Rebuild.... or CTRL-F5 (Shortcut-Setting).

[xnview]

i can't reproduce, settings>General>Rotate images... is checked, right?

[infosauger]

i can't reproduce, settings>General>Rotate images... is checked, right?

Yes, and newer pictures are roteted correctly.
I would really like to show you the effect in an online meeting.

UPDATE:
I added the current DateTime to the EXIF-Information and now XnView always displays the images with correct orientation.