Connect to "half" of server??

This is very weird. I used to be able to use CMD-K to "go to server" and then browse whatever Macs were connected on my local net. Easy-peasy, I could move files from one to the other. Lately, when I try, I can connect to the server (iMac-2, say) from my Macbook Pro. I get the list of volumes available. I click the one I want (the iMac itself) and up comes the list of available folders: Applications, Desktop, Downloads, Pictures, etc. But when I highlight the Desktop, it says "0 items." Same with Applications, Documents, and Downloads. HOWEVER, if I highlight Pictures or Movies, up comes those folders' contents, nice as you please. I can understand not being able to connect at all. But how can I see the contents of some folders and not others? I've tried tweaking sharing prefs and folder permissions - nothing changes or works. Help?