Quickbooks Error 15106 is basically a payroll update error. This error occurs when you are updating Quickbooks or when you are not logged in as an administrator in the system or when the spy sweeper creates a problem in the system. There are many solutions to Quickbooks Error 15106- first, you have to log in as an administrator, check out the existence of a spy sweeper in your system because many times it creates a problem, etc. QB error 15106