the true here does that mean it delete the source file?

transferResult = session.PutFiles(file, FileToUpload, true, transferOptions);

Philky001 wrote:

transferResult = session.PutFiles(file, FileToUpload, true, transferOptions);

Yes, it will delete the file (false=copy|true=move).

torix wrote:

Yes, it will delete the file (false=copy|true=move).

Correct.

As per the documentation
https://winscp.net/eng/docs/library_session_putfiles

When set to true, deletes source local file(s) after transfer. Defaults to false.