To run QuickBooks install diagnostic tool , firstly, you need to install the QuickBooks tool hub on your computer. You can download the tool from the Intuit website, and after following the on-screen instructions, you can install it on your computer. Now open the application and navigate to the installation issues menu and then select QuickBooks install diagnostic tool. After doing this process, you will be able to solve various errors in your QuickBooks application and run the program smoothly. Additionally, make sure to use the upgraded version of windows on your computer to run the QB desktop hassle-free.