Good old cluster.exe will be replaced by failover cluster powershell cmdlets. Cluster.exe won’t be installed by default but it is an optional component. 32 bits DLL resources are no longer supported also.
Hardwire drivers support XDDM has been removed in Windows Server 2012. You may still use the WDDM basic diplay only drive that is included in this OS.
Hyper-V TCP Offload
TCP offload feature for Hyper-V VMs will be removed. Guest OS will not able to use TCP chimney.
Token ring network support is removed in Windows Server 2012, who needs it anyway?
this file has been removed, now OS uses the WSK, winsock kernel to provide the same service.
NDIS 5.0,5.1 and 5.2 APIs is removed. NDIS 6 is supported.
In hyper-v, the import / export concept of transporting VM is replaced by “Register / Unregister” command / method.
SMTP and the associated management tools are deprecated. you should begin using System.Net.Smtp. With this API, you will not be able to insert a message into a file for pickup; instead configure Web apps to connect on port 25 to another server using SMTP.
SNMP service and its WMI components will be remoced.
Win32_serverfeature namespace is removed.
wmic command line tool is now replaced with get-wmiobject