Well, 123.hp/setup is the main webpage of HP to help their customers with installation of HP printers, troubleshooting of HP devices, to contact the customer support and to download the updated printer driver. For the first time installation of HP printers, you can visit the 123.hp/setup from your computer's browser and download the HP Smart app. Thereafter you can set up the app as per your printer model, which then describes the step by step method for installing your printer. Apart from this, you can download the latest printer driver software for your HP printer model. The website 123.hp/setup also lets you contact the customer support instantly and check the repair status of your device in no time.