QB Issue Resolution:
The easiest way will be to migrate from QuickBooks Desktop first and then to QuickBooks Online (via Company -> Export Company File to Quickbooks Online). Make sure you have downloaded the latest updates for the Desktop version before migrating to online. QuickBooks Desktop is available for a free 30 day trial if you do not have the software already.
The trial link is:
Resolution for Issue 'How do I prepare for using the data migration service?' available: Yes (Solved).
Source: Intuit Community forum.
How do I prepare for using the data migration service?: this issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the issue yourself by looking for a resolution described below. If it is a complex issue or you are unable to solve the issue, you may contact us by clicking here or by using other support options.Support for Company File
Quickbooks Repair Pro will resolve it efficiently and affordably. Guaranteed resolution of your issue, or you pay nothing!
Error Recovery for Company File [Canada]
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