SFTP from iSeries failes to connect while Filezilla works fine

We have a customer who must transfer some exported data to an outside vendor.
We have set up OpenSSH (5733-SC1) on the customer's server (V5R4).
The outside vendor is using CoreFTP on a Windows server.

We have been going round and round without any success in getting the SFTP to connect.
As this was to be a batch transfer, we generated public key for the user on the IBM server and provided that to the vendor; they say they have installed it.
We used SSH to obtain the vendor's server key and get that into the known_hosts file.

I followed Scott Klement's article: http://systeminetwork.com/article/ssh-scp-and-sftp-tools-openssh

When we run the batch transfer program (ILE RPG spawning SFTP), we get the following errors:

Permission denied, please try again.
Permission denied, please try again.
Received disconnect from X.X.X.X: 2: Too many logon attempts.
Connection closed

(I removed the IP address from that 3rd line.)

The outside vendor wanted us to try without a key. He has removed the key from his CoreFTP server.
When I try an interactive SFTP session from a PASE Terminal (QP2TERM), we get the same errors.

However, FileZilla from my PC using ServerType of SFTP works.

I'd appreciate any help as both the customer and vendor are growing impatient.

Thanks, Scott

________________________________


Scott Schollenberger
Vice President, Research & Development

P: 610-239-9988 x305
F: 610-239-9995
E: SSchollenberger@xxxxxxxxxxxxxxxxxx
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