QB Issue Resolution:
You should be able to upgrade to Enterprise or Enterprise Accountant 2019, but unless you pay someone to help you convert down you cannot open your file with Pro or Premier.
Resolution for Issue 'What versions are compatible with Enterprise 2016 Accountant?' available: Yes (Solved).
Source: Intuit Community forum.
What versions are compatible with Enterprise 2016 Accountant?: 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 Enterprise 2016
Quickbooks Repair Pro will resolve it efficiently and affordably. Guaranteed resolution of your issue, or you pay nothing!
Error Recovery for Enterprise 2016 [Canada]
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