If approval is enabled, your users will be forced to review invoices and approve the coding, before they they will be able to be exported, normally by a smaller group of accountants with explicit permissions to do so.
If you have approval enabled, you will see a new tab on your dashboard labeled Pending Approval
In order to export the invoice, it must be reviewed and manually approved by a member of your staff.
Navigate to the invoice, click Approve.
By approving, the user approves that the GL coding is correct & their name and date/time are captured in the invoice history, to reference which person is responsible for the coding and sign-off of this document.
This approval history log is visible on the History tab of the invoice.
Once an invoice has been approved, it will move into the third tab on the Invoices page, Approved - these invoices may be exported by the accountant or any user who has been given the exporting permission.
Those other users without export permissions will be restricted from exporting invoices from the Approved tab, but may view invoices they have approved.