Recently I ran into two different issues while trying to upgrade/install the NMS Server.exe package. One was an upgrade where I kept receiving the following error: "There is not enough space on drive C:\ to extract this package". There was definitely enough space on the C:\. Another was on a clean install with the error "Windows cannot access the specified device, path, or file. You may not have the appropriate permissions to access the item." I tried a bunch of different things, including checking permissions, running the exe using a unc path, etc. Not sure if there is a better way to do this, but in case this happens to you, I ended up using this utility called 7zip to extract the NMS Server.exe package. Then if you go into the folder that it extracts into, you can run the setup.exe. Both times, this worked. Hope this helps someone at some point.