I just checked that for you. I thought it wasn't necessary but with USPS credentials in the admin I get the same error so apologies there you will need to enter the USPS Username.

I would also update the site to the latest version as 6.8.5 is getting a bit old now.

Andy

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So I signed up for USPS, have entered my username into the USPS admin section in the admin and now get this error:

The tracking system returned the following error : Username exceeds maximum length.

If I enter in a bogus username I get this:
The tracking system returned the following error : Authorization failure. Perhaps username and/or password is incorrect.

There's a note on that here https://www.ecommercetemplates.com/help/usps.asp can you make sure you are on their production server?

Andy

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Thanks for the leads.

If anyone else is having this problem, you'll need to register with USPS's Web Tool API Portal to get your username to enter into the ECT USPS admin.
https://www.usps.com/business/web-tools-apis/welcome.htm

Thanks, and very sorry it took so long to find a resolution.

Andy

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