Most of the time, the QuickBooks Error code 404 appears when the user has not installed the software properly, or there are corrupted files present in the QuickBooks database. To troubleshoot the problem, uninstall the software and reinstall it on your system. Clean all the junk files from your device for QuickBooks recovery. Upgrade your Windows to the latest version available, or you can perform the clean or fresh Windows installation. Hopefully, this will help you to resolve the issue, but if it is not happening, contact the QuickBooks support team for professional help from experienced engineers.