Re: FTP/SSL (FTPS): 425 Unable to build data connection

Giganews Newsgroups
Subject: Re: FTP/SSL (FTPS): 425 Unable to build data connection
Posted by:  Remy Lebeau \(Indy Team\) (re…
Date: Mon, 17 Jan 2011

"jvlad" <dm…> wrote in message

> The server does not send any data on data-channel.

Then the server is at fault.  TIdFTP is establishing a valid connection.

> Everything works good up to the moment when server accepted
> data-connection. At this point client turns PassThrough off initiating
> SSL handshake, the handshake finishes without errors, but after
> that an attempt to read from IO returns 0 meaning EOF.

That means the server is intentionally disconnecting the data connection,
indicating it has finished sending its data.

> At this moment command-channel returns error 425 Unable to
> build data connection: Operation not permitted.

That is a server-side error.  It accepted the connection, but does not like
something about its characteristics.

> It seems to be an ssl issue because all the related commands : AUTH TLS,
> PBSZ 0, PROT P, etc are the same as in my FTPS implementation on
> top of indy9.

Then the fault is on the server end.  Check PROFTPD's logs for errors.  For

Remy Lebeau (TeamB)


In response to

FTP/SSL (FTPS): 425 Unable to build data connection posted by jvlad on Mon, 17 Jan 2011