"That's not a Minecraft skin, silly"

rplatham Updated based on 0.15.90.7:

When selecting "Choose New Skin" selecting the skin that is located in the minecraftpe folder (which is the current custom skin for the player) always gives the error "That's not a Minecraft skin, silly!". Selecting the same skin from another folder does not give this error.

Original Report:
When I wanted to add a custom minecraft skin, it keeps saying that the skin is not a minecraft skin but it is.