I have been using an old version of Adobe Dreamweaver to edit the code for my websites. Suddenly it quit working. Standalone FTP programs like FileZilla and Coffee Cup FTP worked. I tried changing all the Dreamweaver settings I could think of, but nothing worked. I found other Dreamweaver users had the same or a similar problem:
Dreamweaver 9/CS3 FTP stopped working, cannot connect any more
FTP Errpr in Adobe Dreamweaver
This question had no working answers, but as some of these answers suggested, I contacted my web hosting company WebHosting Pad.com, and they gave me the answer. I had not changed the FTP settings for weeks, maybe months, before the FTP quit working. The answer to the question, “What folder on the server do you want to store your files in?” had been /home/me/public_html. It turns out that the correct entry was only public_html, without the folders above it.
Computer Handyman Blog 