Well, this is a question rather hard to aswer. Why? Because the fisrt part of your post has little to do with the second part.
You make an action link. Than you probably have an action called ExportTo in your current controller. Where you pass the PDF in the ReportType parameter. This seems to work, since you don't get any routing resolution error.
Now for the second part: how can we tell, what's wrong, as long as we don't know what's in the action method (supposing you have properly added RDLC support to your application)?
By the way, the error you got on the screen will be most likely more explanatory as you have call stack and many other additional information. And by the way, you have debugging. Use it!
I suggest you follow the steps described here:
Prototype MVC4 Razor ReportViewer? RDLC[
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