QB Desktop - won't open file - says operation not permitted

Thanks for posting here in Community space, Lina016.

To isolate the issue, let me guide you through the steps on updating your Windows 10 version to the latest release. Please ensure that your new computer meets the system requirements for the migration to work smoothly.

If the issue persists, you can try performing the migration process again. However, if that doesn't work, we may need to manually move your QuickBooks Desktop (QBDT) Pro 2020 software. Let's start right away:

1. Install your QBDT software on the new computer. 
2. Create a backup company file from your company.
3. Restore it to the new one.
4. Then download the latest tax table after moving your company file.

Additionally, you may also want learn how to keep QuickBooks up-to-date so you have the latest features and product improvements, please visit this article: Update QuickBooks Desktop to the latest release.

If you have additional queries about getting your data back, please don't hesitate to reach us again by leaving a comment below. We're always here to assist you all the way. 

@Lina016 

Your business name.qb2020  is the backup file created on QB Desktop 2020 for Mac. If you have a PC, you need to restore the back file on QB Desktop 2020 for Mac and convert it to You business name.qbb to restore on QB Desktop 2020 Pro/Premier. You can ask a 3rd party provider to convert your data if required.