Q:

Can I sign DLLs that are not open source?

I am trying to add portable areas into my project using MVCContrib but am having problems with the fact that the dll is unsigned.
I am now trying to sign the dll, which means I have to re-sign all the references that it uses (including Microsoft.Web.MVC) - as the Microsoft dll is not open source, for example. does that mean that I cannot sign it? As I am unable to access the source code and create a SNK key for it..
EDIT: I want to sign the assemblies because:
-After looking at this question it seems there are very few (good)reasons for using unsigned assemblies. 
-And I am finding that it has a knock-on effect where any assembly that references the portable area has to be unsigned, and any assembly that references that, and so on... 

A:

Yes.
Instructions on how to do so here. Will leave this up in case anyone else needs it..

