Open HP Support Assistant in Windows by searching for it or by clicking the app's icon in the taskbar. Download the most recent version of the programme from the HP Support Assistant website if it isn't already on your PC. Locate your machine on the My Dashboard page, and then click Updates. On Mac and Windows computers, you can also find and launch Diagnose & Fix on the HP Smart app. Open Diagnose & Fix first, then the HP Smart software. Windows: In the lower left corner, click the Diagnose & Fix icon. macOS: Select the printer you want to fix, go to Printers in the top menu bar, and then select Diagnose & Fix.