QB Desktop ErrorMessage: A QuickBooks company data file is already open and it is different from the one requested or there are multiple company files open.
This error is thrown when multiple users are working on the same Quickbooks file.
If you are getting the following error below it is due to multiple users working on the same QuickBooks file.
To clear this error, please follow these steps:
Ask all users to close QuickBooks (including yourself)
Once this is done, only you should sign back into the company file
After this, please attempt to publish an invoice
Note: The error message will only clear after an invoice is successfully published to Quickbooks.