...
The directions below are not a step-by-step pictorial reference. It assumes you have at least a basic understanding of how to use Windows and computers in general.
Big Deal #1
Permissions. You need to set FileZilla Server to run as a different user. This is not the whole puzzle, however, so simply running FZS under your normal administrator account will not solve your problem. To accomplish this is easy enough. Go to your Control Panel and open Administrative Tools. Open Services and locate the FileZilla Server row. Open the properties page for it (double-click) and go to the Log On tab. Enter a local username and password here that you wish to use. I strongly suggest you make a new user account for this task. Make it an administrator to start with just so you know it works...do proper security later. You will need to restart the FileZilla Server service for this to take effect.
...