How to convert Quickbooks Premier Accountant Ed 2008 to Quickbooks Desktop Pro Plus 2021

You will need to install trial licenses for QBD 2011, 2015 and (probably) 2019 to gradually upgrade your data before opening it in your QBD 2021. Contact us in private and we may share the trial codes.

Hello there, @Horhaydaman.Thanks for taking the time to reach out for support here in the Community. 

Along with what Fiat Lux - ASIA said above, I'd be glad to lend a hand so you can able upgrade from Quickbooks Premier Accountant Ed 2008 to the Quickbooks Desktop Pro Plus 2021version of QuickBooks Desktop and have all the transfer files properly. 

If you upgrade to a newer version (year) of QuickBooks Desktop, you’ll also need to upgrade your company files. The QuickBooks software has a three-year life cycle, and upgrading your company file from the 2008 edition to QuickBooks Desktop (QBDT) Pro Plus 2021 is a big leap. That means you have to convert your data file(s) in stages from 2008 to 2011 to 2014 to 2017 to 2020 and 2021. 

Once done, QuickBooks will ask you to upgrade your company file the first time you open it in your newer version. Also, the option to open your company file in your original version of QuickBooks after you upgrade it is unavailable. You can restore it using the steps below:

1. Make sure all users log out of your company file.
2. Open your new version of QuickBooks Desktop.
3. Tap Open or Restore Company if you don't have a company file open. You can also go to the File menu and select Open or Restore Company.
4. Select Open a company file, then Next. If you have a backup company file (QBB) instead of a company file (QBW), choose to Restore a backup copy and then Local backup.
5. Browse your computer for your company file. Select it and then hit Open.
6. Sign in to your company file as an admin user.
7. Before you upgrade, QuickBooks automatically creates a backup of your existing company file. Then click Change this default location to save the backup in a specific folder.
8. Press Update Now to start the upgrade.
9. When QuickBooks finishes, click Done.

You can now open your company file in your new version of QuickBooks Desktop. If you keep your company files on a server, just move them back.

For more information on upgrading your QBDT files, you can check out this article: Upgrade your company files after you switch to a new version of QuickBooks Desktop. 

Additionally, I’ve got you this article that can help you fix general problems when you encounter issues when opening your company file: What to do if you can't open your company file. 

Fill me in if you have more queries about managing your files in QBDT. I'd be glad to assist you further. Take care always, and best regards.