Opening and Closing Posting Periods: Example 
You want to limit posting to G/L accounts (with a few exceptions) to the current and subsequent period only. The same applies to your customer and vendor accounts. Certain G/L accounts (140100 to 149999), which you need for preparing the financial statements, are to be permitted for the previous period also. Account number 140150, however, is to be excluded from this interval (140100 to 149999). The current period is 01/2000.
You can define the posting periods for these accounts by specifying account intervals. First open all your G/L accounts for posting in the current period and the subsequent period only. You then define your exceptions. by opening accounts 140100 to 149999 for posting in the previous period as well. Enter accounts to be excluded from the interval separately.
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You can do this by making the entries shown below.
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Specify the minimum entry + to open the periods you need for all your accounts.
Open the current period and the following period for all your G/L accounts by entering an account number interval containing all account numbers.
For the interval 140100 to 149999, specify the current, the following and the previous period.
For account 140150, specify only the current and the following period.
For your customer and vendor accounts, use the reconciliation accounts to specify the permitted posting periods. To do this, enter the account type in the column headed A . Then specify the permitted posting periods for the desired account number interval.
Note
For account types D and K , you specify the numbers of the reconciliation accounts rather than those of the customer and vendor accounts themselves. This entry determines the posting periods permitted for the sub-ledger accounts.