For SFTP support on Windows, we recommend CoreFTP's Mini SFTP Server, a free SFTP server that is easy to install and configure.
Download and install Core FTP's mini SFTP server from their website at http://www.coreftp.com/server/download/msftpsrvr.exe.
Now that you have the server up and running you should be able to connect to it from Air Sharing. But first you need to find out your computer’s IP address. The easiest way to do this is to get a Command Prompt window open and then type: ipconfig
Then launch Air Sharing on your iOS Device and tap the Servers button in the upper left corner and then tap Edit in the upper right corner.
Tap the ‘+’ in the upper left corner and choose SSH.
In the URL field enter the IP address of your PC. If you want the Server connection to automatically remember your username and password, enter it now. Similarly, if you want to have a description for the server connection now is the time to enter that.