With most printers you need to install the software and the drivers before you connect the printer.
Switch off and unplug the USB cable from the printer or the PC.
Uninstall the printer from Control Panel/Printers and check with Add Remove programmes that all traces of the Olivetti Software have been removed. If you have it run the registry cleaner part of CCleaner click here.
With the printer off and disconnected re-install the software and the driver.
Plug in the USB connection and switch the printer on. The New Found Hardware Wizard should automatically run. If it doesn't right click Computer, and click on Properties, then on Device Manager and at the top you should find a button for checking for New Hardware (you can also do this via Control Panel).
Post back if this doesn't work.