UAG Connection Errors When Using Internet Explorer 11

Ok, this isnt exactly a SharePoint issue, but it was something that came up while supporting an external SharePoint collaboration site.  I was contacted by my customer recently because they were having issues connecting to a public-facing web site.  Previously they were able to open the page and log in, but after upgrading to IE11, they started receiving the following error.  This error is only present when using IE11, not in Chrome or Firefox:

We were able to narrow the problem down to the UAG (Unified Access Gateway) and there has been an update (SP4) that supposedly addresses this issue: http://blogs.msdn.com/b/testingspot/archive/2013/11/27/forefront-unified-access-gateway-2010-sp4-released.aspx

Until the UAG is updated, here is a work-around:

1) Launch Internet Explorer and go to tools menu and compatibility view settings.  Add the site to compatibility view



2) Hit the F12 key to open the Developer tools on the bottom of the screen

3) Change the user agent option to Internet Explorer 9 or 10

Now you should be able to browse back to the site and login with your credentials.