site folder not found

I have DMX, a G4 Mac with plenty of memory, and system 10.2. I upload to an ASP server using FTP. After working fine for 4 months, suddenly when I make a connection to the server, my files seem to disappear on my side -- just empty folders. If I break connection, leave DMX and reopen the files, I am told that the root folder doesn't exist. I first run through the edit process for the root folder and get same answer. Then I try the NEW button and recreate it but am told that it already exists. If I throw out the DMX prefs, it acts okay again until I connect to the server and everything disappears again -- and stays that way until I throw out pref again.

I tried re-enstalling Dreamweaver but the cycle starts again. What's going on -- any ideas? I really need to upload new files to the website.

My website is http://www.sengei.com/
but I don't see how anything on the site could be affecting this.

Thanks for any insights into this problem. I am without a clue here.

Julie Jones