QuickBooks update error 15215 occurs most of the time while performing payroll update and maintenance release. QuickBooks Error 15215 generally occurs while updating payroll or performing maintenance release. This can be a somewhat lengthy process but it will definitely help if you stick to the instructions provided. The error 15215 in QuickBooks appears because of improper configuration in IE of Microsoft. Often QuickBooks verifies digital signatures of all downloaded files using program get Call Now +1-(800)-993-4190.
QuickBooks Error 15215 generally occurs while updating payroll or performing maintenance release. This can be a somewhat lengthy process but it will definitely help if you stick to the instructions provided. The error 15215 in QuickBooks appears because of improper configuration in IE of Microsoft.

Source: https://www.99accounting.com/fix-quickbooks-error-15215/