So it seems you are using SCP, not SFTP. Can you try SFTP?
Ok then i tried with FTP protocol, i still have an error :
"Transfert failed :
Error code : 4
Error message server : Failure
Asked code : 6"
I tried with the transfert software FLASHFXP and got a message : "A file cannot be larger than the value set by ulimit"
My unix administrator says it doesn't have any size limitation for my normal user.
So it seems it is a bad configuration of my Windows 2000, it is just surprising i do not have problem if i use th root session.
[EDIT]It seems the group of my user (right click on file on a file) isn't recognyze, so i get a limitation for copying [/EDIT]