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SFTP Error: The SFTP session has disconnected unexpectedly (Error code -5580899)


I'm trying to connect to a SFTP server using LabVIEW (LV2023). I'm using the SFTP APIs included in the VI.lib.

I am sure that the SFTP server is working fine. I can successfully connect using FileZilla.


In LV, the returns the following error:



Code: -5580899

set "LVASKPASS_PATH=\\.\Pipe\LOCAL\lvsshpw.<my Windows user>"& set "SSH_ASKPASS=C:\Program Files\National Instruments\LabVIEW 2023\resource\lvaskpass.exe"& set "SSH_ASKPASS_REQUIRE=force"& set "DISPLAY=:0"& "ssh" -p 22 -o StrictHostKeyChecking=accept-new -s <SSH user>@<SSH server> sftp


NOTE 1: In the error description above, I have removed some information for privacy reasons. Removed data is included in the '<' and '>' brackets.

NOTE 2: connection is password-based.









Can you help me?





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Try if you can use OpenSSH for Windows from Power Shell or Windows Terminal SSH

Control Lead | Intelline Inc
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With OpenSSH in Windows Powershell, I receive this error:


"PTY allocation request failed on channel 0"


Any idea?



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Message 3 of 6

Any suggestion? 😞

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Message 4 of 6

From what I found for that error message, the server does not allow an interactive session. I guess that is required for password authentication from LabVIEW.


Does it work when you use sftp instead of ssh from the command line?


You can use key-based authentication instead of username/password. Here is an article how to set that up for a windows server:

You basically generate a key pair and put the public key into a file on the server. We use that approach with cRIOs.

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I don't have any issues running SSH from PowerShell or CMD.


Perhaps you can try to search online.

I did a quick Google and found this. From ssh - How to fix request failed on channel 0 - Stack Overflow

The client is requesting a shell session with a TTY and the server is rejecting it. The server doesn't provide the client with a detailed reason why the request was rejected. You need to troubleshoot this on the server rather than the client.



Control Lead | Intelline Inc
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