I am getting the same error when I try to import my accountant changes to my client's QuickBooks.   Today is the second time its happened in the last week.  The first one I didn't have many changes so I just did them manually on the clients and discarded the accountants copy restrictions on the client's computer.   This time there are many changes that I don't want to have to re-enter.  What is the fix?  I have tried everything suggested here.   First time was with QB 2018 and this time it is with QB 2019.  Has never happened before.  FRUSTRATING