Why Network Scan Utility do not working with Xerox 3550?

I was download software form this site

http://www.support.xerox.com/support/workcentre-3550/file-download/enus.html?operatingSystem=win7x64&fileLanguage=en&contentId=111168&from=downloads&viewArchived=false

Software found my Xerox but showed error about it can't working with this printer model. Why? As well I can't add scaner after installation this soft. Push Add device, Connect to scanner and input scaner IP address, after searching I reciving error "Device do not found".