opened filed but can only see black screen (i can see the layers on the side bar)

[Veni Cee]

Hi Everyone

I'm just testing out the latest PS and I seem to have done something to make my image not appear in the main section.... I can see the layers of my work in the side bar- but only black in the main area.  Prior to saving my file, I unintentionlly chose postcard on one of my layers, which brought up a little black box in the top left corner of the main editing area.... I couldnt get rid of it, so I saved my file to my computer and then when I opened it back up there only a black screen, please help!

see image below:

 

[Stephen Marsh]

@Veni Cee 

Preferences > Technology Previews > Tick the "Deactivate Native Canvas" option

Zoom in and out multiple times until you can see the image. Sometimes this could be white, or red, green or blue.