General Ledger is in balance the end of the prior year but is out of balance the beginning of the current year (Prior year adjustments need to be closed)

Confirm that the prior year adjustment entries are valid. Refer to How can I confirm if I have prior year adjustments in GL? for instructions on identifying the prior year adjustments.
If the prior year adjustments are valid, refer to How do I close prior year adjustments to retained earnings? If the adjustments should not have been posted to the prior year, make the corrections in the application the entries originated.
If this does not resolve the issue, see Why is my General Ledger out of balance? for other possibilities.