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Hey there I wonder if anyone can get me in the right direction. I am setting up both a FTPS Client and Server, FTPS Server using Microsoft’s iis FTP 7.5. On the client side it will be running on Linux and I am using M2crypto for the openssl wrapping (python). I am worried the problem is on the server side (iis7.5) due to the following discovery :

If I host using Filezilla with BOTH the control and data channel being forced to be encrypted it works 100% (100% file transmission), if i use iis as the server everything works up to the point when the data channel takes over... i.e. all data of the retrieved file is already received correctly in my basket! The ftp server just won't send the final '226 Transfer complete.' on the cmd socket. Why? If i force the client or server to close the connection the file is 100% intact....If i use iis 7.5 with forced encryption on control channel all works 100% as long as i don’t force data channel...

Here are some screenshots to demo this... Client View after Kill Client :

pics @

Summary : We can establish the connection, do directory listings, start the upload, see the file (0bytes) created on the server but then the client hangs. If we terminate the client, the uploaded file on the server suddenly jumps up to full size.

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You will start by taking Network Trace and see at what stage it's blocking. It's always better to get a clear picture. I would also like to see the FTP logfile.

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Log Before Force Client script to close : – user59050 Nov 4 '10 at 5:53
after force : – user59050 Nov 4 '10 at 5:56
Another flawless transfer using cerberus as FTP server : – user59050 Nov 4 '10 at 6:27
can you go through and verify if the configuration is good. – Vivek Kumbhar Nov 4 '10 at 6:32
I would also like to check if FTPS configuration is good by accessing the same from a Windows PC. – Vivek Kumbhar Nov 4 '10 at 6:32

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