%APPDATA% is an environment variable. The true location will vary from machine to machine.
On Server 2008 R2, "%APPDATA%\FileZilla", if pasted into an Explorer address line, will probably lead to "C:\Users\<username>\AppData\Roaming\FileZilla"
On Server 2008 R2, "%APPDATA%\FileZilla", if pasted into an Explorer address line, will probably lead to "C:\Users\<username>\AppData\Roaming\FileZilla"