The SFTP account doesn't have delete permission, and the server could have failed the removal instead of replying with Status code :0 and keep the file silently (I can check).
With no delete permission, how to make sure the files are not synced multiple times. Client and server are in different timezone, is it good enough to use Size as criteria Vs either. Thanks.
Disable transfer to temporary file name/transfer resume support, as the error message suggests.
In .NET assemby, you can do that using