VBA ServerXMLHTTP https request with self signed certificate

I'm using a ServerXMLHTTP object to make some http requests on an excel 2007 vba script.

But I need to connect to an https server which uses a self-signed SSL Certificate, so by default I get the message "The certificate authority is invalid or incorrect". Is there a way to configure the ServerXMLHTTP object so that it doesn't requires a CA Certificate?

Some sample code follows:

Set objHTTP = CreateObject("MSXML2.ServerXMLHTTP")
  objHTTP.Open "POST", "https://invernalia.homelinux.net", False, "user", "password"
  objHTTP.setRequestHeader "User-Agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)"
  objHTTP.send ("")

Solution 1:

I used to have this problem for a while, and I only managed to get past it thanks to this:

Set objHTTP = CreateObject("MSXML2.ServerXMLHTTP")
objHTTP.SetOption 2, objHTTP.GetOption(2)
objHTTP.Open "POST", "https://invernalia.homelinux.net", False, "user", "password"
objHTTP.setRequestHeader "User-Agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)"
objHTTP.send ("")

I have found this here setOption Method and getOption Method

Here in this code I have just used SXH_SERVER_CERT_IGNORE_ALL_SERVER_ERRORS but you can try with others more specific:

• SXH_SERVER_CERT_IGNORE_WRONG_USAGE
• SXH_SERVER_CERT_IGNORE_CERT_CN_INVALID
• SXH_SERVER_CERT_IGNORE_CERT_DATE_INVALID
• SXH_SERVER_CERT_IGNORE_UNKNOWN_CA

Solution 2:

Set objHTTP = CreateObject("MSXML2.ServerXMLHTTP")
objHTTP.SetOption(2, objHTTP.GetOption(2) - SXH_SERVER_CERT_IGNORE_ALL_SERVER_ERRORS)
objHTTP.Open "POST", "https://invernalia.homelinux.net", False, "user", "password"
objHTTP.setRequestHeader "User-Agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.0)"
objHTTP.send ("")

Got the above solution to work with a minor change. Instead of:

objHTTP.SetOption(2, objHTTP.GetOption(2) - SXH_SERVER_CERT_IGNORE_ALL_SERVER_ERRORS)

I used:

objHTTP.SetOption(2) = (objHTTP.GetOption(2) - SXH_SERVER_CERT_IGNORE_ALL_SERVER_ERRORS)

Otherwise I get an error of:

Microsoft VBScript compilation error '800a0414' Cannot use parentheses when calling a Sub objHTTP.SetOption(2, objHTTP.GetOption(2) - SXH_SERVER_CERT_IGNORE_ALL_SERVER_ERRORS)

referenced from: SXH_OPTION_IGNORE_SERVER_SSL_CERT_ERROR_FLAGS