Hi Christine 64,

The reason that your accountant can open the file but you cannot is because sage 50 Quantum is 2 versions higher than Sage 50 Pro.  A higher version of sage 50 can open data from lower version but not the other way around.  

A Sage 50 Quantum can open the data from Sage Pro by first upgrading the format of a Pro data to Quantum and then open it.  However, the process cannot be reversed once it is complete.  Ususally, an accountant is eligible to join our Sage Accountant Network and use the Sage 50 Accountant edition, which can be used to open any version of Sage 50 file without changing the format. 

In your case, if your accountant only has a Quantum format of your data file but no pro format, you will have to pick up a date to start a new company file in your pro version, have your accountant print a trial balance as of that day and then use the figures as the opening balance of your chart of account in the new file. 

For your reference, you can follow the link below to have your accountant export the record of the accounts, customers and vendors, and then import them to your new company.  Please be reminded that they are records but no transactions

Exporting and importing accounts

Hope this helps

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