I am a new user so forgive me if I am not too clear about this issue.

I have come to the end of our fiscal year and the accountant has requested a copy of my accounting data file so he can prepare our year end tax return.

The problem is that I want to continue using Sage to enter receipts and create invoices after our year end. What happens if my accountant finds problems in how I entered transactions before and makes corrections to the accounting file and send it back to me? How do I take advantage of those changes the accountant has made to the file without negating all the new transactions I have entered for the new fiscal year? Is there a way to merge things without losing all the new information I have entered? 

Thanks!