I have downloaded 4.3, and installed it

I can see the icon in my sys tray, and all  appears well

(1 channel, server 127.0.0.1, waiting, 0 connection)

 

I enter the sample code in my browser 

(http://localhost/ContactMine2/Contact.fwx)

 

I asks me for username and password (Administrator + my password)

I get error HTTP 500 Internal Server Error

 

Can someone help me with this?