Why does my background go transparent when I merge down layers?

[janellm34036150]

For some reason when I merge down, my background layer goes transparent. I can still see the picture on the main viewing screen, but the thumbnail goes transparent.  I can save the picture, and see it in adobe bridge or Lightroom. However if I try to email it or import it anywhere, it will not upload or be seen.

 

[Barbara Ash]

The layers panel in your screen shot does ont display any pixels so it makes sense that no image is dispalying.

[janellm34036150]

Yes, but the layers had pixels.  They disappear when I flatten the image.  The picture on my main image section is still there.

[Bojan Živković]

What you see is "abnormal". Have you tried to reset preferences what is general advice for all things weird or abnormal in Photoshop? By the way, Background layer can not be transparent.

https://helpx.adobe.com/photoshop/using/preferences.html