You are required to specify a reason any time you perform a transaction (other than reconcile or float). Reasons are user-defined and are configured in the POS Back Office (Applications > POS back Office > Setup > Transaction Reasons).
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Transaction reasons are explanations for a register drawer being opened without making a sale. These reason have a system-generated Reason ID as well as an editable Description. They are accessed and managed in POS Back Office Setup.

Transaction Reasons are managed on a Transaction Type basis as selected from the drop-down menu

To add or edit a Transaction Reason:
Select the Transaction Type.
Right-click in the Transactions Reasons window and select New to create a new Transaction Reason
OR
To edit a Transaction Reason, double-click its row to display the Add/Edit Transaction Reasons form.

Add or change the Description.
Click Save to keep your changes.
To delete a Transaction Reason:
Right-click the Transaction Reason you want to remove and select Delete.