FTP client stopped working

[Brian]

When attempting to access any FTP site via Windows Explorer, I get a message
whose Details section is this: "The connection with the server was reset."

Three notes:

1.Other computers in the same network have no problem accessing the same FTP
servers.
2. When attempting FTP connections via command-line, I get this after
entering the user: "Connection closed by remote host"
3. Even a GUI FTP client I have fails to connect, with this error:
"An established connection was aborted by the software in your host machine"

Ideas?

 

[Brian]

Never mind. It had nothing to do with my computer...well, only indirectly.

We switched IP's last week, so we got new public IP's for our servers &
router.
The network administrator ran the ICW on the server, which automatically
changed the Gateway/Router entry in the (SBS) server's DHCP scope from the
router's IP address to the server's LAN address.

My laptop is the only computer in the office that regularly connects to
different networks - all other computers have static IP's and thus the
correct static gateway of the router's IP address. When I came in, my laptop
got the new address, including the incorrect gateway address, and was thus
using the server as a gateway.

Rather than reconfigure the server to correctly pass through FTP traffic,
the network administrator just reset the router/gateway entry for the DHCP
scope to the router's IP address, and I did a release/renew on ipconfig. FTP
is fine now.

The only problem in all of this is that I am the network administrator, so
it was all my doing, anyway. Too bad. Nobody to blame but myself.