If you are trying to log into USPS Discounted rates but are being given this error:


There was an error when communicating with Pitney Bowes: (bad.request) unable to authenticate user credentials


This can be due to not having your Pitney Bowes account connected with the Shiptheory preferred rates account. To resolve this, go to your carrier settings page and click the Register button and then Already Registered? Sign In on the next page. 


If you are still experiencing issues, please reach out to Support