How to post credentials to prompt window with Invoke-WebRequest
<p>I am trying to build a PowerShell script which logs in to a site and downloads a file. However the site does not have the username / password fields in a form, like most sites. When navigating to the site, it immediately opens a prompt looking like: </p>

<p><a href="http://i.stack.imgur.com/eFdjT.png" rel="nofollow">Authentication Required Prompt</a></p>

<p>My question is how would I send an Invoke-WebRequest to post a username and password and login to the site. Traditionally, I have been finding the username and password by their ID attribute and setting their values but this is not possible with this prompt. Any ideas? Thanks</p>