FileZilla Forums

I love FileZilla, but my main reason for using it has a bug.

I'm download large files (1GB+) from a MS FTP server (IIS 6). The file will download and as it nears the 800MB mark (I can't nail down exactly when, but around this time), FileZilla shows a "Connection Lost With Server" error in the log panel. However, the file is still downloading.

The problem? The file never "stops" downloading. If the file on the server is 1GB, the download will reach 1GB, and continue going. I don't know exactly what it is downloading after the 1GB mark, but the file on my hard drive continues to grow, and now the file is corrupt.

I've tried this on:
Windows 7 build 7100, Quad Core, 4GB RAM
Windows Vista Ultimate, SP1, Quad Core, 4GB Ram
Windows XP, latest SP, AMD K7, 1GB Ram

I am running FileZilla 3.2.6.1

All MS IIS FTP servers have a bug: They claim to support resuming, but in reality they do not. If the connection is lost for whatever reason and FileZilla resumes, the transfer seems to continue where it interrupted, while in reality the server will send the complete file again from the start and append it to the old partial one.

So, what can I do to correct this problem?

If you are not in control of the server you can't correct this problem. You should be able to workaround with 'File exists action' in Filezilla's settings. You can't use Resume.

So, you think changing the action to always overwrite on filesize change or newer version will fix the issue?

that should work, up to you if you want it to be the "always chosen" default action though. I recommend you set it to ask for action as default then set a session answer if you find yourself using an FTP server that fails to properly support resume.