Photostream will not upload from windows PC to iPhone

I have successfully set up Photostream on myPC, and am able to transfer pictures from my iPhone to my PC with noproblems. However, the reverse doesn’tseem to work ---- i.e., photos are not transferring from my “upload” folder tomy iPhone.

The photos that I’m trying to transfer arestandard, medium-resolution .JPG images.

I changed the default folders for both thedownstream and upstream folders to point to an external hard drive. Other than that, I can’t imagine what wouldbe the problem.

Any help would be most appreciated!