Notepad++ NppFTP [SFTP] Connection failed : Error reading socket

Question

Does anyone know why I am unable to connect to my server using the Notepad++ NppFTP plugin with SFTP?

I have a CentOS 6.4 server with SSH on port 22.

When I try and connect using NppFTP I get the following output:

[NppFTP] Everything initialized
Connecting
[SFTP] Connection failed : Error reading socket 
Unable to connect
Disconnected

This used to work when I had my SSH port set to 3264 but when I changed the SSH port back to 22 NppFTP stopped working. All the settings for the profile are correct including the right IP, username, password and port (22).

I can connect with SFTP using FileZilla and WinSCP successfully with these same SFTP details and I can connect with SSH using PuTTY.

I can connect with SFTP to other servers using NppFTP so I believe there is an issue in my server config I'm just not sure where or what.

Answer 1

I looked at the access logs but found no attempt at a connection from NppFTP, I turned the firewall off and still nothing.

In the end I got in touch with my server company and it turns out it was a problem on their end. This is what they had to say:

"This was caused by an IPS rule inspecting the network packets coming into the infrastructure, which helps identify brute force attacks."

Very strange, but after they made the change NppFTP can now connect successfully.