Have you downloaded and installed Microsoft .Net 4.5? I was getting the same issue until I installed the correct .Net version.
I did encounter this error once when doing some early testing and mistakenly installed Operations Dashboard for ArcGIS 10.1.1 on my Windows 7 OS machine w/ArcGIS Desktop 10.0 installed (meant to install on my ArcGIS Desktop 10.1 machine). I assumed error was because Operations Dashboard for ArcGIS 10.1.1 requires ArcGIS 10.1.1 services yet I haven't done further testing to confirm my initial thoughts.