PS 5.5 has suddenly stopped opening .PNG files. I'll go to open a picture, and PS freezes. It will open .PNG files that I have made, but any textures or gradients in .PNG format won't open. It won't open any files that came from a certain person, and only the files that I downloaded from that person. They will open in MS Paint, just not PS. I can open them in MS Paint and change them to .JPG files, and then they will open in PS. Do these files have a virus or something?