I suggest doing some troubleshooting steps to ensure the script error pop-up won't show anymore, Barry.

Since, you're using a 2017 version of QuickBooks Desktop pro, here a steps for you to follow in fixing this error:

1. In the search box next to the Start menu icon, type Control Panel.
2. Click the Control Panel. A page will appear on the Start Menu under the Best Match title.
3. At the top of the control panel window, type change in the search box.
4. Under the Program & Feature section title, select Change or remove a program.
5. Locate the QuickBooks installation you want to repair, and then double-click it to launch the installer.
6. When the QuickBooks Installer/ Maintenance Wizard launches, click Next to see the options Repair and Remove. Select Repair and then click Next to complete the process.
7. Once completed, restart your computer, even if Windows does not prompt you to do so.

Also, I'd recommend reaching out to an IT professional for guidance about the script error.

Refer to this article for guidance in creating a backup of your company file in QuickBooks Desktop.

Feel free to reach out if you still have concerns about creating a backup file in QBDT. We're here to help you out.