Year-end could not be done because to opening balance is not balanced, but in the system opening balance Income & Expenses cannot be seen.
To Enable Income & Expenses Account in Enter Opening Balances:
Go to Housekeeping, Setup, General Setup.
Change the Starting Period to 2 or more.
After you have changed the setting, you may start to edit the opening balance.
Make sure the figure of the opening balance is tally.