USPS Ground Advantage sent through Endicia fails on one profile while every other USPS service works. On that profile, remove and re-add the Endicia USPS services, and do not re-add First-Class (Ground Advantage replaced it).

Problem

USPS Ground Advantage through Endicia fails on a profile, while all other USPS Endicia services on that profile keep working. The message reads:

Missing or Invalid element: Mail Class

Cause

The Endicia USPS service settings on the profile lost a valid Mail Class for Ground Advantage, so the request is rejected. Removing and re-adding the Endicia USPS services rebuilds the settings on the profile with a valid Mail Class. First-Class should not be re-added on its own, because Ground Advantage replaced First-Class package service.

Fix

  1. Open the affected profile.
  2. Remove every Endicia USPS service from the profile.
  3. Re-add the Endicia USPS services. Do not re-add First-Class on its own.
  4. Re-rate the package that was failing and confirm Ground Advantage returns at the expected rate.
  5. Test a shipment that was failing before, then run a small batch before going back to normal volume.

What you should see

Ground Advantage rates and ships on the profile with no "Missing or Invalid element: Mail Class" message, and the other USPS Endicia services still work.

Related articles

  • USPS international multi-box shipment fails on package weight (Endicia)
  • USPS shipping fails: something went wrong or object reference error