Hi, I tried to backup data via samba. Target file grows over 4G but when the size hits 4G, it's shrinked to 0 byte and grow again but sooner or later back up program reports error. I had a chance to look at the problem and what I found is NT sends write command with 0 length and series of writeX... and write command again and so on. I saw the comment, 'write command with 0 length is truncate' so I guess NT is trying to truncate the file before write real data. But as you aware, write command has 32bit offset field. So It can't handle bigger than 4G size file. I tried the same thing between NT servers and it only sent writeX command. Is it a negotiation problem? I tried 2.2.2 and 3.0alpha. Yes, just copying bigger than 4G file works fine. Soohoon.