Rebex.Net.SftpException: Key exchange failed. Requested service is not implemented

+1 vote
asked Jul 12, 2016 by Ritesh (290 points)

I am not able to connect to the SFTP server. I am getting the error messages as "Rebex.Net.SftpException: Key exchange failed. Requested service is not implemented. ---> Rebex.Net.SshException: Key exchange failed. Requested service is not implemented."

But when I connect using the FileZilla FTP client it works fine. Could you please help me out on this.

Many Thanks

Applies to: Rebex SFTP

1 Answer

0 votes
answered Jul 12, 2016 by Lukas Matyska (43,090 points)

Can you please ensure that you are using FileZilla with SFTP protocol and not the FTP protocol?

If you are using really SFTP, please let us know.

If you are using FTP, please use the Rebex FTP/SSL component (instead of Rebex SFTP).

commented Jul 13, 2016 by Lukas Matyska (43,090 points)
Yes, append asterisk '*' to the source path, like this ftp.Download("/XYZ/*", "C:/ABC").
commented Oct 5, 2017 by mike_saroyan (100 points)
I am having this identical issue with a connection that had been working for over three years without a glitch. When I use FileZilla or WinSCP with SFTP option, I am able to connect, but with Rebex, I get the error message "Key exchange failed. Requested service is not implemented". I am using Rebex version 3.0.4700. Below is the log entry:
2017-10-05 12:25:51.647 Opening log file.
2017-10-05 12:25:53.690 INFO Sftp(1)[10] Info: Connecting to clientXYZ.com:22 using Sftp 3.0.4700.0.
2017-10-05 12:25:53.831 DEBUG Sftp(1)[10] SSH: Server is 'SSH-2.0-OpenSSH_7.4'.
2017-10-05 12:25:53.831 INFO Sftp(1)[10] SSH: Negotiation started.
2017-10-05 12:25:53.924 DEBUG Sftp(1)[10] SSH: Group exchange.
2017-10-05 12:25:54.080 DEBUG Sftp(1)[10] SSH: Negotiation failed: Rebex.Net.SshException: Key exchange failed. Requested service is not implemented. ---> Rebex.Net.SshException: Requested service is not implemented.
   at Rebex.Net.SshSession.1xzy5U(Byte[] , Int32 , Int32 )
   at Rebex.Net.SshSession.i12XcZ(Byte[] , Int32 , Int32 )
   at Rebex.Net.SshSession.1rsOcLZ(1VEj6UZ , Object[] )
   at Rebex.Net.SshSession.2aErfC(OCfHX )
   at gbMKS.2dBnlEZ.qzm1d(SshSession , Byte[] , Byte[] , Byte[] , Byte[] , Byte[]& , Byte[]& , SshPublicKey& )
   at Rebex.Net.SshSession.qzm1d(Byte[] )
   --- End of inner exception stack trace ---
   at Rebex.Net.SshSession.qzm1d(Byte[] )
2017-10-05 12:25:54.111 ERROR Sftp(1)[10] SSH: Rebex.Net.SshException: Key exchange failed. Requested service is not implemented. ---> Rebex.Net.SshException: Requested service is not implemented.
   at Rebex.Net.SshSession.1xzy5U(Byte[] , Int32 , Int32 )
   at Rebex.Net.SshSession.i12XcZ(Byte[] , Int32 , Int32 )
   at Rebex.Net.SshSession.1rsOcLZ(1VEj6UZ , Object[] )
   at Rebex.Net.SshSession.2aErfC(OCfHX )
   at gbMKS.2dBnlEZ.qzm1d(SshSession , Byte[] , Byte[] , Byte[] , Byte[] , Byte[]& , Byte[]& , SshPublicKey& )
   at Rebex.Net.SshSession.qzm1d(Byte[] )
   --- End of inner exception stack trace ---
   at Rebex.Net.SshSession.qzm1d(Byte[] )
   at Rebex.Net.SshSession.14Ad4fZ()
   at Rebex.Net.SshSession.Negotiate()
2017-10-05 12:25:54.143 ERROR Sftp(1)[10] Info: Rebex.Net.SshException: Key exchange failed. Requested service is not implemented. ---> Rebex.Net.SshException: Requested service is not implemented.
   at Rebex.Net.SshSession.1xzy5U(Byte[] , Int32 , Int32 )
   at Rebex.Net.SshSession.i12XcZ(Byte[] , Int32 , Int32 )
   at Rebex.Net.SshSession.1rsOcLZ(1VEj6UZ , Object[] )
   at Rebex.Net.SshSession.2aErfC(OCfHX )
   at gbMKS.2dBnlEZ.qzm1d(SshSession , Byte[] , Byte[] , Byte[] , Byte[] , Byte[]& , Byte[]& , SshPublicKey& )
   at Rebex.Net.SshSession.qzm1d(Byte[] )
   --- End of inner exception stack trace ---
   at Rebex.Net.SshSession.qzm1d(Byte[] )
   at Rebex.Net.SshSession.14Ad4fZ()
   at Rebex.Net.SshSession.Negotiate()
   at Rebex.Net.Sftp.1J4sBU.qzm1d(ZD5WJ )
   at Rebex.Net.Sftp.2eOMSNZ(String , Int32 , SshParameters , ZD5WJ )
2017-10-05 12:26:10.304 ERROR Sftp(1)[10] Info: System.InvalidOperationException: Not authenticated to the server.
   at Rebex.Net.Sftp.Qv0o9Z()
   at Rebex.Net.Sftp.TZuYIZ(Qu2Ci , ZD5WJ , String , Stream , Int64 , Int64 , 27NpLhZ )
commented Oct 6, 2017 by stepantalalayev (3,940 points)
You are using Rebex SFTP Version 2012 R3 , which is 5 years old. Can you please try connecting with the current version? You can download the trial  from http://www.rebex.net/sftp.net/download.aspx and try connecting using its SftpWinFormClient sample.
commented Jun 13 by malhameed (100 points)
I have updated to the latest Rebex SFTP  but i'm still getting same error "Key exchange failed. Requested service is not implemented." any help?
commented Jun 13 by Lukas Pokorny (92,430 points)
Please create a log using Sftp object's LogWriter property (as described at https://www.rebex.net/kb/logging/) and either post it here or mail it to support@rebex.net for analysis. Thanks!
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