11-17-2020 04:24 PM - edited 06-09-2021 02:47 PM
Why am I seeing and How do I resolve the "Stamps.com: Authentication failed" error?
When you get the Authentication Failed error there can be two main culprits to account for.
You will need to update your password in ShipStation. You will go to Settings>Shipping> Carriers & Fulfillment> Stamps account> settings, click reauthorize, enter your new password in both fields, and hit save.
In this scenario, you will follow the same steps as scenario 1 but with one difference. Once you click reauthorize, if you did not also change your password, you will just enter your current Stamps.com password in both fields.
If after these steps you are still unable to use your Stamps.com account, contact Stamps support at (888) 434-0055 for further assistance.