I too have this error. When do you think this error could be fixed?
(please don't take this as I'm pressuring you or anything to fix this, I'm just curious)
Some more info just in case:
OS: Windows 2008 R2 server
.NET version: 3.5
Application is using the dll from the download page (version 5.1.4).
I run the application every day at a set time (9am) once, I started to get these errors
Could not open session, WinSCP process terminated with exit code 3 and output "", without creating a log file.
I use this dll in my C# application. The application connects to an SFTP remote server and downloads a bunch of files (around 20).
Application is scheduled to run via the MSSQL Server agent and not via Windows Scheduler.