Cannot connect on port 20 - all firewalls have been removed.


I cannot open port 20 on my windows machine and as such cannot FTP.
I have uninstalled McAfee Security Center (no software firewall now), disabled Windows firewall and opened ports on router. The router is definitely working correctly as my laptop is connecting to FTP on port 201. We have even setup the machine as a DMZ (all ports open on router).

Any ideas?
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giltjrConnect With a Mentor Commented:
You may want to install wireshark ( and do a packet capture.  See what is going on.

As for "opening port 20".  Port 20 is only used for active ftp data connections and is used by the source as the source port.  The client will open a high port (port >1023) and listen and the server will connect from port 20 to the port the client is listening on.  The client tells the server what port it will be listening on on the PORT command.

Do you have any other firewalls between the ftp client and the ftp server?  It could be that the firewall on the server's side is setup not to allow active ftp data connections.  You may need to get another ftp client that supports passive ftp data connections and try that.  MS command line ftp client only supports active.

IE can be configured to use passive, so you could try that.
Do you want people to FTP to you, or are you going to FTP to somewhere? If you are letting people FTP to you, then you have to setup FTP server, at port 21. If you are going to purely FTP to other servers, there is no need to open port 21 on your machine.
smaccaAuthor Commented:
I just want to retrieve/upload files to an external FTP server.

I am also hosting my own FTP server but I dont really care if that works or not as I will rarely use it - would only use if client had to download a big file or site from my development machine.

This is causing me MAJOR headaches as I cant FTP from my development machine and I am a Software Engineer / Web Developer - and this is one of my main tools of trade.

Any help appreciated - thanks for your comments.

Cheers. Steve.
The Lifecycle Approach to Managing Security Policy

Managing application connectivity and security policies can be achieved more effectively when following a framework that automates repeatable processes and ensures that the right activities are performed in the right order.

then there's no need to open any ports on your machine. Some questions. Is the external FTP server newly set up? Or have you been uploading/downloading from it before this happens? Is the external FTP server purely an FTP server only? If not, you can check whether any other protocols are allowed, like HTTP etc. Connect to it using browser or something.  I am not too good at network troubleshooting ,however basics like whether the router is configured properly to route FTP traffic etc comes into mind. If you have router logs, it also an avenue to look for clues.  Sorry can't get you further than this.
smaccaAuthor Commented:
Q: Have you been uploading/downloading from it before this happens?

Q: Is the external FTP server purely an FTP server only?
I assume it is FTP and Web Server.

Q: If not, you can check whether any other protocols are allowed, like HTTP etc. Connect to it using browser or something.  
I will try using my browser.

Thanks for your help.
smaccaAuthor Commented:
I am sure this is a Windows Service Pack 2 problem. There are notes on SP2 that talk about how it closes ports now by default. I really have tried everything else including 'Add Port' on the 'Internet Connection' in network/control panel.

This is really causing me problems as I need to FTP from this machine - OUCH!
ghostdog74Connect With a Mentor Commented:
how is the result of using browser? if you can at least browse something from that server, your network connection is ok. Since you had mentioned that you have disabled Windows Firewall in your first post and also you have been using the FTP so some time, then i don't think its the windows firewall.
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