If you want to know how to fix QuickBooks update error 15240, follow the instructions mentioned below:

• On the tools menu click on the option that says ‘internet options’.
• Click on the ‘advanced’ tab.
• Navigate to the bottom and you will see ‘use SSL2.0’ and ‘SSL3.0’. Choose these two options.
• Press the ‘apply’ button and then save the changes by clicking ‘ok’.

If you face any complication while proceeding with this method then contact QuickBooks technical support number to get help from a technical assistant.