It's a delight to see your post here, nbautista.

The QBB file is a backup file used in QuickBooks Desktop (QBDT). Right now, there is no direct way of opening and importing this into your existing QuickBooks Online (QBO) account. You'll need to open the file in the Desktop version, then import it to QBO.

If you no longer have the QBDT software, you can use our trial links to open the backup file, then export the file from there.

Here's how to export the file:

1. Restore the backup copy.
2. Click the Company menu.
3. Choose Export Company File to QuickBooks Online.
4. Follow the prompts so you can connect to the Online version.

Once done, you can import from the QB program itself (a QBW file) to QBO.

Here's a link with the details on how you can move your Desktop file to Online: Move your QuickBooks Desktop file to QuickBooks Online.

You are always welcome to visit us again if you need help with something else. Have a good one.

@nbautista 

Restore the backup file on the trial license as mentioned by nbautista. Then utilize TPE for QB Desktop to export the data out to XLS and TPI for QB Online to import the data into your current QBO.

https://transactionpro.grsm.io/qbd