Re: ZoneAlarm blocks FTP apps

From: Michael J. Pelletier (
Date: 01/17/05

Date: Sun, 16 Jan 2005 22:17:18 -0800

Reader wrote:

> I'd like to use FTP Explorer ( to upload files to my web
> site,
> however, ZoneAlarm blocks the connection. I have been shutting down ZA to
> allow FTPX to access the remote web server. Basically, ZA lets me
> actually log in to the remote web server (ie. name/pass are accepted) but
> then it
> prevents the remote file listing from showing in FTPX's pane. If I quit
> ZA,
> I can view the remote file list normally and upload/rename/etc. I tried a
> different FTP client (FTP Commander) with the same result: connect okay,
> but
> no file list unless I quit ZA. I'm running ZoneAlarm with Antivirus, the
> latest version (v5.5.062.004) and a "manual update" check says I have the
> latest version. I'm running Windows XP Pro + SP2, with the Windows
> Firewall
> disabled. Any ideas? As a side-note, I used to be able to use FTPX and
> ZA just fine in the past, but that was before I had XP -- and I'm not
> going to
> drop XP just to gain FTP access. ;)

When you setup the rules did you allow BOTH port 20 and 21 (Active FTP).
Remember that FTP uses TWO ports. Also, you should review the difference
between passive vs active FTP. I am not sure which one you are using.
Active FTP uses port 21 and port 20. One port is for commands and the other
is for that transfer of data.

If you are using passive FTP then you need to allow the dynamic ports
through as well at port 21....