I also got the correct answer using Win98/VFP 7.0 sp1

Were you able to get XML to work?

USPSAddress CorrectedAddressXml(string accessCode, string address, string city, string state)
Given a valid street address, city, and state, returns an USPSADDRESS structure with STREET, CITY, STATE, and SHORTZIP and FULLZIP elements. If an error occurs all elements in the structure are empty. Use accessCode of '0' or '9999' for testing.

struct USPSAddress
This structure contains the return value of the CorrectedAddressXml method.

Members of the structure are:

string Street - full street address, could be multiple lines separated by Html BREAK elements 
string City - full City Name 
string State - two-character state abbreviation 
string ShortZIP - standard five digit ZIP code (NNNNN) 
string FullZIP - ZIP+4 code (NNNNN-NNNN) 

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>I ran your code and got '95118-2403' returned. I'm running WIn2kSP3 and have Soap3 installed. What windows version/SP are you running? What Soap version?
>
>>I have tried several web services. They all return the same thing.
>>Here's an example of one:
>>
>>local ZipCode as ZipCode, WS
>>WS = newobject("Wsclient",home()+"ffc\_webservices.vcx")
>>WS.cWSName = "ZipCode"
>>ZipCode = WS.SetupClient("http://webservices.eraserver.net/zipcoderesolver/zipcoderesolver.asmx?WSDL", "ZipCodeResolver", "ZipCodeResolverSoap")
>>?ZipCode.FullZipCode("9999", "1444 Annapolis Way", "San Jose", "CA")
>>
>>This returns: OLe error code 0x80a13bc Unknown COM status code.
>>Anyone have any ideas?