USB Display Adapter not working on Windows XP
 

Hi there,
I just bought the USB Display Adapter to extend my Windows XP PC.
It is a Dell Optiplex GX520 running Microsoft Windows XP Professional Version 2002 Service Pack 3.
I have downloaded and installed DisplayLink_7.6M2.exe
During installation my existing monitor went black 2 or 3 times.
Then the installer window disappeared.
It didn't notify me that the installation was successful or ask me to reboot.
So I rebooted anyway, and I can now see 3 new programs running in Task Manager:
DisplayLinkManager.exe
DisplayLinkUI.exe
DisplayLinkUserAgent.exe
However, there is no new icon in the notification area/system tray.
I have then connected the new monitor 2 via the USB 2 socket on the front of the machine.
I confirmed that it was set to the VGA port.
Unfortunately, it is not working.
Any help that you can provide would be greatly received, otherwise I will have to return the product to the merchant.
Kind regards,
Will.