Problem trying to upload a video file

Hi all,

I've just uploaded one video file successfully today and was going to upload another one. However, it doesn't seem to be working. I'm not sure if it's to do with my SmartFTP or to do with my webhost/space. We have the room to put it up as we have recently upgraded to 5 GB but I just don't know what the problem is. The message I am getting is this:

[20:40:17] STOR Bedford-Save-Me-24Nov05.wmv
[20:40:17] 125 Data connection already open; Transfer starting.
[20:40:17] 10240 bytes transferred. (58.1 KB/s) (172 ms)
[20:40:17] 426 Connection closed; transfer aborted.
[20:40:17] Transfer failed.
[20:40:17] TYPE A
[20:40:18] 200 Type set to A.
[20:40:18] PASV
[20:40:18] 227 Entering Passive Mode (84,22,184,70,14,178).
[20:40:18] Opening data connection to Port: 3762
[20:40:18] LIST -aL
[20:40:18] 125 Data connection already open; Transfer starting.
[20:40:18] 2336 bytes transferred. (14.6 KB/s) (156 ms)
[20:40:18] 226 Transfer complete.

The file comes up, I am asked to overwrite the one that is there (as it transfers one over but with 0 bytes, says transfer is complete but nothing has gone over. The file is there, named and everything, but says 0 bytes. Anyone have any idea what's happening?

Thank you kindly for your help/advice/support.