Click Settings -->Shipping Settings
- Click on "Configure Real-Time Carriers."
- Make sure that USPS, FedEx, USPS, etc has a green checkmark above the USPS logo and that you have set Do you use real-time shipping rates, order tracking, or label printing? > to YES.
- Save and Continue
- On the next screen, enter your API username in the "Username" field. Fill in the remaining information, including your business address, and select the shipping methods you want to enable.
- When you're done, click the Save and Continue.
- The next page will be your Shipping groups page. If you already have your Groups configured click on the Group you would like to add Your configured shipping carrier to. If you have not configured your Shipping Groups do so at this time and click Save and Continue when done.
- In each zone, configure which Shipping methods you would like to offer. Click Save and Continue on each zone(s) once you have added your shipping methods.