Error 15215 QuickBooks happens due to a conflict with any third-party application that is running in the background in your system. Especially, QuickBooks error 15215 occurs while downloading and installing the payroll update as the application requires high bandwidth and any minor technical glitch can crop up the error. One simple and shortest way is to reboot your system. It will help you resolve technical errors. Additionally, you may also try to run QuickBooks as a Windows administrator. For that, simply, right-click on the QuickBooks icon and click Run as administrator. Also, click Yes over the confirmation window. Once you follow all the steps the QuickBooks error code 15215 should resolve.