Do not repeat sending files after reconnection ?

Hi
I am new to the forum and I am honored to do so
I want to ask a question how can I not re-send files when they are sent for the first time (i mean when missing files are completed when uploading or downloading again)
Sometimes my computer crashes while sending files. For example, when I try to send them again, I start from the first one. :|

In GUI?
You can use transfer settings "Newer and updated files only" or synchronization:
https://winscp.net/eng/docs/task_synchronize