Enter your Knox e-mail username including @knox.edu and password when prompted.
Single click on Win_Sophos_Installer.exe.
Click Save to save the file on your machine.
Close your browser.
Find and double click the dowloaded file.
The installation program will now automatically run. A black window may open. This may take several minutes. Once the program has completed the installation, a shield icon should appear in the Taskbar. Right Click on the icon and select Update Now.