So you will need to use an FTP program that support the use of SSH keys and we recommend FileZilla. Here we will explain the basic steps to upload files to your website hosted by K12USA, using FileZilla with SSH keys. First download and install FileZilla (https://filezilla-project.org/) and Putty (http://the.earth.li/~sgtatham/putty/latest/x86/putty-0.62-installer.exe) to your local computer. Then you will need to generate SSH keys (http://kb.k12usa.com/Knowledgebase/Creating-Using-SSH-Keys) and send us your public key so we can add it to your account. Now that the server will allow access with your key, your Windows workstation needs to know to use the key. The simplest way to do this is with "Pageant", which is part of the PuTTY package. It is an authentication agent that many programs use including FileZilla. To use Pageant, first start it from your start menu. It will launch in the System Tray, and looks like a computer with a hat on it.
Double click it it will open up its key list. Click on "Add Key", find your private key, then click "Open". It will then ask for your passphrase. After you enter your passphrase, you'll see your key in the list.
You can also set Pagent to open automatically every time you open you computer, by creating an Startup Group open automatically every time you open you computer, by creating an Startup Group
"C:\Program Files (x86)\PuTTY\pageant.exe" "{Path to private ppk file}"
Open FileZilla click on "File" then "Site Manager"
Enter in the appropriate information.
Host: <domain name>
Port: Leave Blank
Protocol: SFTP - SSH File Transfer Protocol
Logon Type: Normal
Username: <supplied username>
Password: Leave Blank
Click connect and you should now connect to the server in your home directory. And now you can transfer files to the website\<domain name> directory.