If QuickBooks Desktop Payroll won't update, it may be due to internet connectivity issues, outdated software, or file corruption. To resolve this, check your internet connection, ensure QuickBooks and payroll updates are current, and verify that your company file is not damaged. Following these steps should help restore your payroll update functionality. For personalized assistance, dial 1.855.738.2784. A certified QuickBooks expert will help you get your payroll updates running smoothly.