do all opening balances have to be entered in a new company file at the same time

I have a corrupt company file so for this new financial year 17/18 I have set up a new company file. I have only been using MYOB since 8/5/17 so its new to me !

I have only been with my current organisation since that date.

I have not had chance yet to reconcile all 16/17 accounts so my question is do all opening balances have to be entered in a new company file at the same time.

I have the bank and liability accounts done but not all the assets and my GST is a bit of a pickle. Can I enter these later when I know they are right.

The whole purpose for a new company file is for it to be clean.

Thanks in advance