Dreamweaver has some very "unique" aspects to its ftp layer 
We at
PVII have had issues regularly over the years and have isolated them as
relating to hardware - specifically routers or cable/DSL modems. If the
hardware gets out of sorts, or if the ISP has reset IP address, you
would need to reboot the router or modem. If a router goes bad, DW FTP
is going to go with it and you will not be able to connect until you get
a new one.
It is definitely Dreamweaver. There are never issues with any other
programs, be they dedicated FTP clients or editors such as TopStyle,
Coffee Cup... any of them. None exhibit the problems Dreamweaver does.
We keep after it because we do consider it important to our workflow -
but it can get exasperating. I'm sure if Adobe knew what the problem was
they'd fix it - but apparently they don't.
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