How do we close a month so that we do not accidentally post a transaction/entry to a month that has already been reported to the Finance Committee or audited by our external auditors?

In the fiscal year setup (Finance > Maintenance > Fiscal Years > Details), there is a field called "Open Period Date." Once the month is closed, you can update that to the next month. For example, if August is closed, you can change the open date to 9/1. This will allow you to enter invoices/receipts/credits in the closed month but you will not be able to post them unless you re-open the month.

The same concept applies to future months or years.  You can enter invoices/receipts/credits in the future but you will not be able to post in a future year it is not open.  You can post in future months as long as they are within the open period of your active fiscal year.

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