An erroneous setup of Microsoft Internet Explorer is the major cause of QuickBooks Error 15215. The digital certificates on all files are normally double-checked by QuickBooks. To secure your computer and its data, these procedures are done for all downloaded programs. It's possible that the verification is incomplete, or that a problem may develop throughout the process. As a consequence, the verification may stay incomplete. It's also feasible that there will be no authentication at all. The error notice appears as a consequence of insufficient or incorrect verification.