Even though many users prefer modern browsers, QuickBooks relies on Internet Explorer settings to connect with update servers. If these settings are outdated or incorrectly configured, Error 403 can occur. Adjusting advanced settings, enabling SSL, and ensuring Internet Explorer is set as your default browser can resolve the issue. For smoother performance, always update Internet Explorer to the latest supported version. By keeping these browser settings optimized, you reduce the risk of QuickBooks Update Error 403.