QuickBooks Error Code 15240 is an error that can occur when a user is trying to update or download payroll updates in QuickBooks software. This error can be caused due to a number of reasons such as incorrect date and time settings on the user's computer, incorrect SSL settings, internet connectivity issues, or issues with QuickBooks files.

When this error occurs, users may see an error message on their screen that reads, "Error 15240: The payroll update did not complete successfully." This error can prevent users from downloading or updating their payroll tax tables, which can cause problems with payroll processing.