There are various screens that allow you to return serial numbers to store:

1. Serial number screen

Go to Stock>Serial Numbers. Select the item then search for the serial number in the lower grid.

Click on the serial number then click the Return button.

2. Requisitions

Go to Requisitions. Search for the requisition number. Click on the item in the lower grid then click the Return button.

3.  Staff screen

Go to Staff. Search for the staff member.

You can return serial numbers from the Items tab, Line Items tab and Serial Numbers tab. Click on the item then click the Return button.

Whichever screen you choose to return the serial number, you will be prompted to enter a warehouse and a reason for the return.

4.  Returning an unregistered serial number (available from V1.8)

To return a serial number that has never been registered on Opex go to Stock > Serial Numbers and click on the item code. 

In the lower grid click the Return Unregistered button.