Have tried over 15 times to migrate to online from 2012 qb to 2020 trial qb, all to no avail, Spoke to intuit and they mailed to say this is a job for odyssey but

Hi there, @GERRY63.

Thanks for coming to the Community for your concern. I understand the need to migrate from QuickBooks 2012 to the 2020 version. The eight years gap in the data file is the main issue why you're unable to achieve this. 

To give you an idea, QuickBooks works on a three to four updating cycle. For instance, 2012-2016-2020. Hence, you'll need to restore 2012 to a 2016 version and make a new back-up file. Then, restore the new back-up in the 2020 version.  

Let me show you how: 

1. Sign in to Windows as an admin user, then download the 2016 version of QuickBooks. 
2. Follow the on-screen instructions to install it.
3. Open the new QBDT and click Open or Restore Company. You can also go to the File menu, then pick Open or Restore Company. 
4. Tick the button for Open a company file, then click Next.
5. Locate the company file, then choose Open.
6. Log in as admin, and hit Update Now to start the upgrade.
7. Click Done once completed.

Follow the same process when restoring 2016 to the 2020 version. Consider checking this article for more detailed instructions: Upgrade your company files after switching to a new version of QuickBooks Desktop.

For future reference, read through this article: Update QuickBooks Desktop to the latest release. It helps you learn about keeping your software updated to get the latest features for a better experience. 

Let me know if you have additional questions. We're always here to guide you more. 

@GERRY63 

1. Which QB Desktop version you have? US, UK, CA, or else?

2. Where is your company located?