FTP Login Problem?

My FTP program only intermittantly allows me to connect to my server. This seems to be a problem with my computer, not my server.

When I reboot my WindowsXP machine, I can FTP to my website, no problem. But when I try to FTP a 2nd time, or FTP to a different domain on my server, I get blocked.

This seems like some kind of firewall problem, but how can I figure out what is blocking it? I turned off AVAST antivirus, I disabled SpywareBlaster, disabled SpyBot Search %26 Destroy resident protection. None of this helped.

I am using Core FTP and also Coffee Cup FTP. This happens with both programs: 1st time after rebooting I can FTP to my server just fine, but 2nd time after rebooting, I am unable to FTP with either program. I upgraded to the latest versions of both programs, and this did not fix it.

I am able to FTP to my server just fine with other computers on my LAN without problems. Something is messed up with my own computer.

How can I find out what is blocking my FTP?

FTP Login Problem?virus

There are different modes for FTP, active and passive.

You are most likely using active mode since you are being blocked (by some firewall?). Active mode makes the FTP server attempt to connect back to your computer from source port 20/tcp.

Passive FTP instead allows you to initiate both connections. If switching to passive mode doesn't solve the problem, try switching to another FTP Client (I recommend FileZilla), since it could also be a problem with CoreFTP/Coffee Cup FTP.