sorry if this is in the wrong topic, i have a prob with my photoshop an no doubt its gona be sumthin nooby 2 fix.. for sum reason i could before but now i cant put a layer over another layer, i get the no smoking sign but without the ciggy in the middle;p now a number and an envelope apear in the top left of all my layers.. will some one tell me how to fix this please? thanks in advance