Does IIS FTP fail a lot?

I had an IIS5 server in a remote location that I used to FTP to, using WS_FTP Pro and Win2000. Now, in that same remote building, I have a new Win2003 server with IIS6 on a new machine, and my PC uses WinXP with IE6's built-in FTP.

Problem is, under BOTH the old and new setups, FTP seems to constantly fail during sending files up to the server. The only constant to the remote machine is our connection. It is only 768K and the whole company uses it to get out to the Internet at that remote location.

Any ideas why my FTPs would fail so much. I literally have to retry sometimes 5 times, and it will work on the 6th try. It is driving me up the wall!

Thanks.

 

Windows FTP doesn't handle passv mode very well. If you sre trying to send files trough a firewalled box with only port 21 open then you might have problems. Better to use an ftp client rather than built in ftp of XP.

 

Actually, that server is in a "red zone", between the Internet firewall and another internal firewall. Everything is locked down, so I am sure only Port 21 is open for FTP. I am mainly using the FTP functionality built into a commercial piece of software, and that fails the most. I only occasionally fail using IE - IE seems to be most reliable.

Are there any other ports I could ask the WAN guys to open to help? What technology is an alternative to passv?