Access denied error with MSXML2.ServerXMLHTTP

Question

I'm receiving an intermittent "msxml3.dll error '80070005' Access is denied." error. The object always posts back to the same domain. I don't quite know why it works sometimes and why it fails other times. This is Classic ASP - VBScript

set xmlhttp = CreateObject("MSXML2.ServerXMLHTTP") 
xmlhttp.open "POST", "http://xxxx.com/GetCacheValue.aspx", false
xmlhttp.send "" 
strCaptchaText = xmlhttp.responseText 
set xmlhttp = nothing

Answer 1

Here's something I snipped from a Google search result:

Security tightened when posting data using the ServerXmlHttp object

Security in the implementation of the MSXML 4.0 SP2 ServerXmlHttp object has been enhanced to check the Internet Explorer security policy setting for submitting non-encrypted form data.

A security policy setting of "Disable" or "Prompt" for the "Submit nonencrypted form data" option will result in an "Access Denied" error message when attempting to post form data using the ServerXmlHttp object.

This is a change that can potentially break existing code that uses earlier versions of the ServerXmlHttp object (such as prior released versions of both MSXML 3.0 and MSXML 4.0) to post form data when the Internet Explorer security policy setting for submitting non-encrypted form data is not enabled.