Prezi and Forefront TMG2010
Our IT staff have just started using Prezi (Prezi - The Zooming Presentation Editor). We are having a problem with using via Forefront TMG2010 where either it simply doesn't load or if it does it will prompt for authentication when trying to upload pictures (for example).
I've seen other sites do a similar thing and to get around it created a rule in TMG that sits above the main web access rule. This rule has the following settings:
Protocols: HTTP, HTTPS
From: Internal, Local Host
To: Domain Name Set (which includes prezi.com)
Condition: All Users
On other sites this gets around the authentication issue, but not it seems with Prezi.
The actual error is: 12209 Forefront TMG requires authorization to fulfill the request. Access to the Web Proxy filter is denied.
If I change my proxy to Synetrix's proxy I have no problems using the site.