Hard 120603 - Invalid Package Reference Value [Solution]

When processing UPS orders, you might come across the "Hard 120603 - Invalid Package Reference Value" error.

This error happens when the Customer Order # exceeds the length of 35 characters when using UPS Mail Innovations. 

To solve this, you can either:

a) Use shorter Customer Order numbers

b) If that's not possible, remove or replace the reference as this article indicates: https://support.techdinamics.com/solution/articles/227983-adding-reference-numbers-on-labels-step-by-step-guide-