Attempting to run Deployment Manager on Server 2008 R2 error:
MMC Could not create the snap-in. The snap-in might not have been installed correctly.
Name: Deployment Manager
This is what I call a windows 7 Administrator problem.
To resolve this you have to right click the deployment manager and choose run as Administrator. You can also right click and set the properties, hit the advanced tab and choose Run as administrator and it will do it every time.