Recently I needed access to my Apple iCloud on my Amazon AWS Work Space, which runs the default Windows Server 2008 R2. When I downloaded the installer from Apple at https://support.apple.com/en-us/HT204283 and then tried to launch iCloudSetup.exe I received an error regarding the version of windows not being supported. After some research I found a great reference regarding how to work around this issue from silvaonline.ch.
One step that was a bit confusing was getting Orca installed. Orca is part of Microsoft Windows SDK for Windows 7 and .NET Framework 3.5 SP1, but is not installed automatically. After installing the SDK you will need to search the directory that the SDK was installed in for the Orca installer ( orca.msi ).