The error implies that the username or password are incorrect. That isn't something that I could help with since I can't verify your credentials.
Are you able to connect on live web pages? If so, then the issue may be the host name and not the username or password.
If you had a connection working anywhere else (a web page, etc.) then I could take a look and figure out why it doesn't work in Dreamweaver, but when it doesn't work anywhere it strongly suggests the username or password are incorrect. Perhaps try resetting them.
Are you able to connect with phpMyAdmin? What is the host name that appears on the top of the page in phpMyAdmin? That is the one you should use in your dreamweaver connection. Dreamweaver doesn't actually need a Remote connection to the database. It uses FTP to upload a web page to the server and connects directly through a url, so sometimes "localhost" will work in Dreamweaver when navicat requires a full domain.
