Wanted to post a quick update to this. Your VBScript code doesn't look incorrect, the 400 error is likely due to the XML you're sending. Is there any chance you can post the actual raw XML that you're sending over? That is usually more helpful to figure out the problem than the raw code.
Also, I updated your post to remove your API key, username and password for security purposes. I highly recommend changing your login information for Constant Contact. These are public forums and by posting that information here, it could be viewed by anyone and crawled by search engines. This information could potentially be cached and stored for people to look up on many websites. As a general best practice, you should never post a username, password or other identifying information on any forums, public or private, to avoid having your information stolen.
P.S. - the original response to this post was removed. The information in it was not applicable for the VBScript question that was posted.
... View more
Unfortunately it isn't possible to do this with the join my mailing list code that's generated within your account. The code that takes a user to the registration form by pressing the GO button is non-editable.
However, if you'd like to implement this by using your own add contact code using our API, you could set the captcha and subsequent registration form up on your side and use the API to add the contact to the approvpriate list(s) in your account. We have a wrapper and sample 'add contact' code available in .NET and PHP if you're interested.
API Support Specialist
... View more