Why can't I change the lockscreen background image of my Lumia 930 ?

[Windows Central Question]

The default one shows a feather floating on water. It's very pretty but I'd like to change it. I can change it with a screenshot or a picture I took, but not with a file I transfered from my computer to the phone. I tried storing these files in the screenshot folder but it didn't change anything. Is it a matter of format ? They're currently .jpg and .png.

 

[MohamedWaheed]

You can't use PNG file for lock screen. Also copy your images to saved images folder and try again.

 

[ven07]

Add the pictures you want to the camera roll and try again. Use a file manager to move them there from within the phone