by juhouh » July 10th, 2014, 1:38 pm
If you're trying to use a file type that has no dimensions, it doesn't work and gives you exactly that error message. The reason why this happens to you is most likely that you're using a wrong url. Every url you put between img tags must end to .png, .jpg (or to any other type of image file)
If you still can't get it to work, give me that link to the image and I'll make it work for you