Comodo v2.4.18.184 breaks my FTP client [RESOLVED]

I am very new to Comodo but formerly used ZoneAlarm with no problems. I find that when Comodo is active that I can’t upload files to my website. The filenames get transferred but the files on the remote end are overwritten as zero byte files. ???

When I disabled (exited) Comodo, the file transfers proceeded normally and successfully.

My O/S is Windows 2000 Professional, so I am using Comodo v2. MY FTP client is WS_FTP95 LE. This has always worked fine under ZoneAlarm. Comodo did not give me any alerts nor any indication that anything was being blocked. But the fact that I can repeatably reproduce the failure by just turning on Comodo and the failure disappears when Comodo is turned off makes it pretty clear that Comodo is somehow blocking my FTP.

When I look at Application Control Rules, I see that WS_FTP95.exe is Allowed for all destinations 0.0.0.0 - 255.255.255.255 for all Ports 0-65535 for Protocols TCP/UDP In/Out.

When I look at Component Control Rules, I see that everything listed is Allowed including: ws2_32.dll, ws2help.dll,WSFTP32.dll, wshtcpip.dll, and wsock32.dll.

So I will be very grateful if someone can tell me how to fix this problem so that I can use my FTP client without needing to turn off Comodo to do so. Private email replies are invited at zephyr[ at ]pcez.com or I will also check back here for any answers. Thanks in advance for any help.

Wow! I fixed it myself. Cool.

I looked again at all of the settings for my FTP client and noticed under the Advanced Settings Tab there is a check box to “Allow Passive Transfers”. The box was unchecked, so I checked it and tried again to upload my test file. Bingo! It uploaded perfectly and was a functional file on the web server. Issue Resolved.

The FTP Help file for that setting says the following:

“Passive transfer is necessary for some firewall and gateway configurations and when you get failed data channel errors.”

That’s exactly what I was getting. Happy Happy Happy now. I hope this info helps someone with a similar problem. This problem is now resolved and this thread should be closed.