I'll give you the steps on how to resolve the error, LB1234.

Before we begin, it's recommended that QuickBooks is updated to the latest release. You also need to install and run the QuickBooks File Doctor for us to resolve the issue as quickly as possible.

Then, proceed to these steps:

1. Remove extra spaces after the company name and before the company file extension. To do this, close QuickBooks and open the folder where the file is saved. Right-click on it and click Rename. Once done, check if you can open the file.
2. If the error persists, please proceed to succeeding steps in this article until the issue is resolved: Error -6000, -82 or -6000, -106 when opening or accessing the company file.

Please let me know if you need more help with this. We'll make sure you're able to open the file and create a backup copy of it.