Connecting from Server results in Connection failed

We have a new installation of WINSCP V 5.13.2 (Build 8455)
The complete Installation runs smooth on one machine that is not behind a Firewall.
Configuration is as
Protocol: FTP
Encryption: TLS/SSL Explicit
Port #21
If started behind firewall on a different Server i get the follwing error messages after starting login on the Windows client:

Connection failed.
Command not implemented.

Port 21 is supposed to be open in Firewall. Could there be any other reason for this messages?
And yes I searched already for this error messages and didnt find any hint where to look for next.

Any help appreciated.

Please attach a full session log file showing the problem (using the latest version of WinSCP).

martin wrote:

Please attach a full session log file showing the problem (using the latest version of WinSCP).

Here is my log. Thanks in advance for the help

martin wrote:

Please attach a full session log file showing the problem (using the latest version of WinSCP).

I answered this a guest... see post above.

Still no idea what to do

Softhak wrote:

< 2018-11-13 10:08:04.670 220 Microsoft FTP Service
> 2018-11-13 10:08:04.670 AUTH TLS
< 2018-11-13 10:08:04.670 502 Command not implemented.
> 2018-11-13 10:08:04.670 AUTH SSL
< 2018-11-13 10:08:04.670 502 Command not implemented.

There's no problem on WinSCP side. Your FTP server does not have TLS/SSL enabled.

Dear Concern,
I am constantly getting an error message of "Server unexpectedly closed network connections" after logging to WinSCP application after 30 sec.

Kindly help in getting this resolved as I am not able to use the application due to constant failure of network connections.

Regards

Vicky Agarwal wrote:

I am constantly getting an error message of "Server unexpectedly closed network connections" after logging to WinSCP application after 30 sec.

Please start a new thread for your specific problem and attach a full session log file showing the problem (using the latest version of WinSCP).