Hi there,
I use WinSCPnet Assembly in SSIS-Script Task. Assembly has been installed to GAC and has been added as reference to my SSIS-Script Task. ScriptTask uses 
ExecutablePath property in 
SessionOptions.
WinSCP-Version: 5.19.5 - Automation
Windows-Version: Win 10 Enterprise v.20H2
Visual Studio 2019 - v.16.9.3
As soon as my SSIS Task starts in SSIS ControlFlow, I get the following Windows Error Popup:
    WinSCP: SFTP, FTP, WebDAV, S3 and SCP client funktioniert nicht mehr. Ein Problem hat die richtige Ausführung des Programms verhindert. Schließen Sie das Programm.    
*In English, this must be something like 
    winscp doesn't work anymore. a problem has prevented this program from running properly. close the program.    
SSIS says that 
    Package execution completed with success.    
My ScriptTask is very basic, it just has to upload files from a local directory to a FTP remote directory.
Can you please give me advice how to debug this error?
Thanks in advance,
Martin