Editing the portalalias entry probably isn't the most direct way to fix it, but in my case, adding the key to the web.config did not fix the issue immediately, however after updating the portalalias entry - it was a non-issue. Perhaps i could have rebuilt the solution again and it would have been fixed, but i chose to alter the entry.

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Also, you might want to change the project setting so that Cassini does not use dynamic ports and configure it to use the same port all the time.  There are other reason to do this as well, since it is possible that a port is assigned that is blocked by the windows firewall.