Commented Unassigned: The connection either timed out or was lost [25137]

This error seemed to crop up with we changed from the 2008 version of msmdpump.dll to the 2012 version. I can't verify as i can't get it to work period on either version. Is there a hardcoded url type that the addin is looking for or something? see the attached picture for the full error text.
Comments: ** Comment from web user: dodom **

I attempted to actually save the information in the .odc file and received the same error. As far as IIS we are using basic authentication.

I had one of our developers look at the source code. He just looked at the portion of the code that is used when you push the 'filter pivottable' button. He compiled it in .net 4 and it worked! He mentioned you were using .net 2, so he tried a couple of .net versions and 4 finally worked with that part. So, i'm assuming if you were to have a .net 4 version, maybe the problem would be solved. We must have something on our servers that we updated (recently as it worked before, and only for remote connections, local connections work fine), that is incompatible with .net 2.

is there any way you can compile a .net 4 version?

Thanks