Let's resolve the error you're having to update your QuickBooks Desktop (QBDT) to open your company file, @spoulton.

Can you tell me more about the error you're having when trying to update your QBDT? That will surely help us resolve the error you're having.

Here are some solutions that you need to check to update your QuickBooks Desktop (QBDT) successfully:

• Check the system date and time on the computer. An incorrect system date or time on your computer can interfere with the update process.
• Verify your internet connection. Visit Chase banking. If you can't open it, you won't get updates from QuickBooks. Contact your Internet Service Provider (ISP) for help.
• Check the settings of your Internet security and personal firewall software.

For detailed guidance on how to proceed with those solutions, check out this article: Fix QuickBooks Desktop Update Errors.

To further check the latest available release for your version, and how to set up automatic updates, schedule future automatic updates, or manual updates, refer to this article: Update QuickBooks Desktop to the latest release.

Once done, try opening your company file, if you still get an error, see the following article for more troubleshooting steps that can help you resolve it: What to do if you can't open your company file in QuickBooks Desktop.

Let me know in the Reply section if you need more help opening your company file or updating your QBDT. I'm always glad to help in any way I can. Have a great rest of the day!