QuickBooks Error 15276 usually happens when a software update or payroll fails, frequently as a result of firewall or antivirus settings interfering, insufficient user rights, or an inactive payroll subscription. Make sure your payroll subscription is active and launch QuickBooks as an administrator to begin troubleshooting this issue. Turn off any firewall or antivirus software that might be preventing the update for the time being. Because QuickBooks depends on Internet Explorer for connectivity, use the QuickBooks Tool Hub to perform the \"Quick Fix My Program\" and check your browser\'s settings. Do a clean install of QuickBooks to get rid of any corrupted update files if the issue continues.