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lantervjFlag for United States of America

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Windows 7 FTP just stopped working

I'm using Windows 7 Home Premium SP1 and I connect to a Windows Server 2008 IIS FTP server.  This has been working just fine.  All of a sudden I get connection errors.  Other programmers are still working just fine.  I'm using the CFeclipse plugin but I tested FTP in the DOS command prompt.  I can connect just fine and log in as anonymous.  But any other FTP commands (get, put, etc.) just hang.  I'm stumped and need a little help debugging this problem.

I checked the event logs on the server but nothing jumps out at me.  I don't see anything on my Win 7 "windows errors" log but I'm not sure how to run the event viewer.
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Steve Smith
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Load event viewer (start run eventvwr.msc) and
Connect via FTP and try all commands that have been failing/stalling
Go back to event viewer as you will know the date/time stamp of the actions to investigate further
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Nothing at all
The problem is in the data channel when you can authenticate but not transfer files or fetch a directory listing.  The DOS command line FTP client always uses Active Mode data channels.  That means when it wants to transfer data, it sends its IP address and the port number it is listening on to the remote server.  The remote server then attempts to connect to that address.  So either something  like a firewall or security software is blocking the connection attempt or the client is sending its private IP address and the server just can't connect... so for example if your client is sending a 10.x.x.x address or 192.168.x.x then the FTP server just won't be able to connect back to your computer unless it is also on the same private network.

Most modern FTP clients default to using Passive Mode data channels where the server specifies the IP address and port and the client makes a second outbound connection to the server.  Firewalls and security software tend to be more willing to allow outbound connections than inbound. Maybe the CFeclipse can do Passive Mode?
Yes, I read about this and it sounds likely.  I have tried turning off the windows firewall without success.  Today's version of CFeclipse doesn't allow us to control passive/active.  In the past we have always had to turn off passive when creating a connection.  I will see if I can determine the IP address being used.  Keep in mind that all was well yesterday til the afternoon when it just started giving connection errors ("cannot list contents of the folder").
I moved my computer to another location and everything works fine. There has to be something in the Cisco firewall at the server site blocking that traffic from my house. Would it be port 20 traffic for data?
It would be something over 1024.  You were probably thinking 20 because that's the local port that the FTP server uses for outbound Active Mode data channel connection.  You can see what the windows command line client used by starting it with the -d flag on the command line and then looking at the 5th and 6th sets of numbers on the PORT command... multiply the 5th by 256 then add the 6th.
Well, I hope this helps someone in the future.  My Netgear WGR614 had a problem.  I did a hard reset and all is well.  The main difference was losing WEP on the wireless and going to WPA2.  I don't have any idea what the REAL problem was.  Thanks for all your responses.
I've requested that this question be closed as follows:

Accepted answer: 0 points for lantervj's comment #a39050180

for the following reason:

Strange problem/solution that didn't really match my original question.
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AlexPace
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