QuickBooks Error 12002 is an error code that occurs when there is a problem with the internet connection while trying to update QuickBooks or download payroll updates. It indicates that QuickBooks is unable to access the server due to connectivity issues, firewall settings, or internet security settings. This error can disrupt the update process and prevent QuickBooks from functioning properly. Troubleshooting steps such as checking internet settings, firewall configurations, and disabling security software can help resolve this error. Error 12002 can also be fixed by consulting the QuickBooks community or requesting technical support at +1 855-948-3646.