Ignore: fixed - [Invalid Security Certificate]

[mandanarchi]

    Set myHTTP = CreateObject("msxml2.xmlhttp")
    Set myDom = CreateObject("MSXML2.DOMDocument")
    myDom.async = False
    myDom.Load (myxml)
    myHTTP.Open "POST", "https://link-removed.aspx", False
    myHTTP.Send (myDom.xml)

I use this code to send xml orders to one of our suppliers (there's more to it, but this is the relevant part)
One of them isn't working today, I emailed their tech guy and he tried telling me that I'm sending invalid xml and gave me the last order they'd received. The order was sent on 29/10/08; we've sent well over 1000 since then with no issues until now.
The security certificate for the site I post the messages to expired last night and that's the only thing I can see that has changed. Obviously there's nothing I can personally do about that.

I haven't got a copy of the error message, I asked our sales guy not to try and send anymore over, but the error occurs on the 6th line.

So 2 simple questions.

Could I be right about the certificate causing our problems?
And is there any vba I can use to add an exception (like you can in IE / Firefox)

[mandanarchi]

Never mind. The tech guy finally got back to me and is sorting it.