A customer's SFTP site just started kicking back with the error in the subject.
I assumed they had changed something on their end, so I connected to their site with the WinSCP GUI.
I confirmed the changes, connected successfully, then viewed the Session Settings.
I updated the settings for their FTP site in my EDI Settings page.
I re-ran the EDI Report and got the same failure.
I asked them to check their settings and confirm them with me.
They sent back the updated settings, which matched what I got from the WinSCP GUI.
After speaking with their tech guy, I tested in Visual Studio's IDE and connected with no problem.
I assumed I had updated the application and forgot to push it to the server, so I went ahead and rebuilt it and pushed it to the server.
The IDE application successfully connects to two other SFTP sites.
I am at a complete and total loss. Does anyone have any suggestions?
From the server, I get this (full, redacted log attached):
< 2022-01-19 14:49:39.822 Script: Searching for host... . 2022-01-19 14:49:39.822 Looking up host "ftp.**customer site**.com" for SSH connection . 2022-01-19 14:49:39.838 Connecting to **customer IP** port 22 < 2022-01-19 14:49:39.853 Script: Connecting to host... . 2022-01-19 14:49:39.853 We claim version: SSH-2.0-WinSCP_release_5.19.5 . 2022-01-19 14:49:39.885 Remote side unexpectedly closed network connection . 2022-01-19 14:49:39.885 Knocking FTP port. . 2022-01-19 14:49:39.916 FTP port opened, will suggest using FTP protocol. < 2022-01-19 14:49:39.916 Script: Server unexpectedly closed network connection. < 2022-01-19 14:49:39.916 The server rejected SFTP connection, but it listens for FTP connections. < 2022-01-19 14:49:39.916 Did you want to use FTP protocol instead of SFTP? Prefer using encryption.
< 2022-01-19 14:49:38.797 Script: Searching for host... . 2022-01-19 14:49:38.799 Looking up host "ftp.**customer site**.com" for SSH connection . 2022-01-19 14:49:39.041 Connecting to **customer IP** port 22 < 2022-01-19 14:49:39.079 Script: Connecting to host... . 2022-01-19 14:49:39.080 We claim version: SSH-2.0-WinSCP_release_5.19.5 . 2022-01-19 14:49:39.107 Remote version: SSH-2.0-CerberusFTPServer_12.0 . 2022-01-19 14:49:39.107 Using SSH protocol version 2