Couple of links that might be relevant:

Issue whereby IE can't parse compressed Ajax : http://robmzd.blogspot.co.uk/2010/02/invalid-character-error.html

Problem with Web Optimization and .less : http://michaeljbaird.com/blog/mvc4-and-bootstrap-less-source

>Thank you. Finding solution to the "ASP.NET Ajax client-side framework failed to load" turned into a nightmare. I am reading a couple of thread (in another forum) where there are tons of suggesions. But so far, no solution. I think it all started with installing DOTLESS package. Maybe I will have to go back and remove it.
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>>What he's saying is he had to change things for source control (TFS) to make it work. If you do what I mentioned in an earlier post, it should work...that and change references to point at the new DLL.
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