I designed and manage two websites and always uploaded files through Dreamweaver's ftp (using Dreamweaver CS 4). While on maternity leave I did not do anything with the websites. Now I am trying to make some updates to the websites and the ftp is no longer working, on either site. I did not change Dreamweaver settings at all.
I downloaded FileZilla and am not able to connect with the servers using that software either.
I tried connecting to ftp.irs.gov (as suggested here: Troubleshoot FTP problems | Dreamweaver CS4 and earlier ) and was able to connect with FileZilla but not Dreamweaver. Dreamweaver gave me "there is a problem with login or password" error instead of the ftp error I had been getting with the other sites.
I double checked my firewall (running Windows 7) and both Dreamweaver and FileZilla are "allowed".
These things sure are frustrating, but you've just got to persevere. If I have this problem, I usually check a few things, like the password and username, then check if I can use those to log in to the hosting control panel etc. Perhaps something has changed with the web hosting since you last logged in. I would recommend you contact the web host and get them to help, as they are in the best position to sort out what's going on. It really should be part of their service to make sure you can connect with your server.