Automate SFTP transfer

Since there is no native ability in WinSCP to run as a service, I'm considering running it from Windows Scheduler. I would like it to run in keepuptodate mode so that it's continuously watching the source folder for changes. If I schedule WinSCP to run the session (with a keepuptodate switch), say every 10 minutes, what happens if WinSCP is still running from a prior launch? Will the new attempt to start it cause any problems? Will it open a new session? This will be running on Windows 2008 R2 server.

Both instances will try to make the update. It is not a good idea at all. Why don't you use synchronize instead? Also use scripting, not GUI.