You might receive QuickBooks error code 1406 when there is a significant update in the firewall setting, antivirus program, other security services, etc. Moreover, the issue is also triggered by improper installation, corruption or damage in the QuickBooks files, and inadequate permission to the download folder.
To fix the QuickBooks install error 1406, switch off your computer's antivirus and security programs. Now, download, install QuickBooks diagnostic tool, and run it on your PC. Moreover, check and repair the damages in the registry and ensure QB Desktop has all the permissions it requires. This should resolve the QuickBooks error 1406 (installation issue).