USPS:
Full Request: API=RateV3&XML=<RateV3Request USERID=""><Package ID="0"><Service>PRIORITY</Service><ZipOrigination>97402</ZipOrigination><ZipDestination>28730</ZipDestination><Pounds>0</Pounds><Ounces>2</Ounces><Container>Flat Rate Box</Container><Size>REGULAR</Size></Package></RateV3Request>
Full Response: <Error> <Number>80040b1a</Number> <Description>Authorization failure. Perhaps username and/or password is incorrect.</Description> <Source>UspsCom::DoAuth</Source> </Error>