We are facing this issue that files are not uploaded and downloaded until server re-start is done.
In logs we are getting below error :
Error: WinSCP.SessionLocalException: WinSCP process terminated with exit code 3. There was no output. Response log file C:\Windows\TEMP\wscp055C.0350F1F9.tmp was not created. This could indicate lack of write permissions to the log folder or problems starting WinSCP itself.