We have a need of a SFTP client running on Windows, which automatically polls for a new file on a designated SFTP location (setup in Unix) every x minutes. Can you please help me identifying such a client.
Microsoft Windows has a tool named "Task Scheduler".
You can write a batch file that attempts to download the file you seek. Then you point-and-click-and-clickity-click until you've informed Task Scheduler you want that batch file run every n minutes.
As for a SFTP client you could try PSCP as part of the Putty collection.