Unable to access password authenticated site with web browser

When using the web browser Vision Component i am unable to access a particular https website that requires user and password.

I get the following error

Unauthorized

This server could not verify that you are authorized to access the document requested. Either you supplied the wrong credentials (e.g., bad password), or your browser doesn’t understand how to supply the credentials required

any ideas what i can do to resolve this, running V8.1.4