After installing the Ontolica Preview solution you can proceed with the installation of the Preview Back-end Installer. Open the Preview Back end Installer folder (installation package) and run the installer. You need to run this installer on all Web front-end machines in your farm. If your farm consists of more than one Web front-end server, select the Complete installation option (Gatherer and Conversion services) only on one of them and Typical installation option (only the Conversion service) on the others. The Complete installation option will prompt you for the SharePoint farm account credentials. The provided account must be SharePoint farm account and also local machine administrator account and will be indicated in the installer. In some scenarios it might be necessary to provide the Fully Qualified Domain Name (FQDN) instead of the NetBios domain name in the Service Doman filed.