UPS suddenly with no notice has dropped the API used for the Zen Cart UPS module. My newsletter did talk about this but our intrepid developer, lat9, has just released the new module this morning. Each website will need to get Oauth credentials. This is a brand new mod and you should remove the files for the old UPS and UPS XML mods when you install this.
Getting the credentials is not an easy procedure however. You have to use or create a UPS account. Creating one for this actually requires two accounts and it took me 30 minutes to get through it all. One thing I really disliked was that you have to give UPS a payment method, either a credit card or paypal account, during setup. Due to this complexity, I will not do it for clients but refer them to UPS customer service instead.
I don’t know, however, how many folks use UPS enough to justify a shipping account – I don’t even remember specific clients who have it turned on. I did have one contact me yesterday – if you still have UPS active, your customers may run into checkout problems. My client said the buyer couldn’t even get to the shipping page, but I saw no error messages that made me think that’s what happened. But when I tested it in a demo cart, it did indeed hang up when trying to get to the shipping page in checkout.
So at a minimum, you must remove the module in your Zen Cart.