I worked on a TIFF image in Photoshop then saved it as a JPG, which I intended to upload to a web site using the Lr4 export feature. The file is in the correct folder, I can see it there in Windows Explorer, and Photoshop is fully aware of it. However, I cannot find it in Lr4. I did a synchronize folder, which did not discover it, then I tried importing it as a new file and it will not show up in the import screen. How do I get this file to show up in Lr4?