how to send test request to usps test server to access ZipCodeLookup API?
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<br/>
i have registered myself with <b>usps.com/webtools</b> and get username/password.<br/>
when i am sending test request to usps test server, i am getting error "<b>Error getting USERID attribute</b>" <br/>

<code>
http://testing.shippingapis.com/ShippingAPITest.dll?API=[API_Name]&XML=[XML_String_containing_User_ID]"
</code>
<br/>

 i am sending request like this (userid is dummy in this case)<br/>
<code>
http://testing.shippingapis.com/ShippingAPITest.dll?API=ZipCodeLookup&XML=`<userid>`018BITOC5420`</userid>`
</code><br/>
how to sent test request with xml userid?