When the software installer does not start, QuickBooks Error 1601 happens. This is frequently caused by a lack of rights, corrupted installation files, or issues with Windows Installer. QuickBooks cannot properly launch or update due to this problem. Usually, it can be fixed by updating Windows installation, fixing the software, or running the installation as an administrator. Call 1.855.738.2784 to speak with a QuickBooks expert if you need assistance.