I had the same error : "cwd" not found in the log file
the problem was with the Installed winscp version, I have replaced the winscp.exe from the .NET assembly / COM library and my problem was solved,
The version of C:\Program Files (x86)\WinSCP\winscp.exe (5.5.5.0) does not match version of this assembly C:\Program Files (x86)\WinSCP\WinSCPnet.dll (5.7.3.0).
You can disable this check using Session.DisableVersionCheck (not recommended).
the problem was with the Installed winscp version, I have replaced the winscp.exe from the .NET assembly / COM library and my problem was solved,
The version of C:\Program Files (x86)\WinSCP\winscp.exe (5.5.5.0) does not match version of this assembly C:\Program Files (x86)\WinSCP\WinSCPnet.dll (5.7.3.0).
You can disable this check using Session.DisableVersionCheck (not recommended).