One of the worry, which an Accountant had, was the user can change the QuickBooks transactions anytime (if he/she has the access right) even the account had already been closed.
A method to prevent changes is to set a Closing Date in your QuickBooks data file. Example: In the month of Oct 2008, you can set a Closing Date as of 30 Sep 2008. This will prevent user to enter data on or before 30 Sep 2008.
To set a closing date, simply go to Edit menu | Preferences | Accounting | Company Preferences tab | click on “Set Date/Password” button and set the closing date and password accordingly.
QuickBooks will prompt for password when user try to save a transaction that is fall on or before the closing date.
To further control the security, QuickBooks Administrator can set the user don’t have the ability to edit or delete transactions that were recorded before the closing date in the user profile.