Custom background gives error?

[LolicOnii]

I'm trying to put an image I found online as my background (instead of the clouds), but when I open Test to see how it looks, I get this error. One out of four images I tried worked, but I cant see why these others wouldn't

http://i.imgur.com/QTHN41j.png

[Helios]

So what you do is you open your Sprite folder, paste the image in there, and rename it Background1.png (exactly like that). And if it asks you to replace the file, do it. That should be all you have to do.

[LolicOnii]

Yeah all of the ones I tried were all named Background1.png. But only one of them worked

[ryujiknight]

I think they have to be a certain size